[
{
"id": "scopus-2026-a-transverse-piconewton-force-revealed-in-anisotro",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr2026",
"entry_type": "article",
"title": "A transverse picoNewton force revealed in anisotropic Womersley flow",
"year": 2026,
"venue": "Scientific Reports",
"volume": "16",
"issue": "1",
"pages": "",
"doi": "10.1038/s41598-026-47474-x",
"doi_url": "https://doi.org/10.1038/s41598-026-47474-x",
"scopus_url": "https://www.scopus.com/pages/publications/105035817120?origin=resultslist",
"authors": "Saqr, Khalid M.",
"abstract": "The fluid-dynamic quantity that regulates endothelial mechanotransduction remains unsettled. Wall Shear Stress (WSS) characterizes boundary traction but does not represent the volumetric inertial structure of arterial blood flow. Meanwhile, blood exhibits direction-dependent stress under physiological shear, suggesting that the classical Womersley solution of the Navier-Stokes equation may omit constitutive mechanisms relevant to near-wall dynamics. Here, I derive an anisotropic extension of Womersley flow by introducing a tensorial viscosity into the incompressible Navier–Stokes equations. By evaluating the nonlinear interaction of velocity and vorticity within a near-wall control volume, I demonstrate that anisotropic viscosity produces a non-trivial spectral signature in the transverse forcing, maintaining power across higher-order harmonics. While macroscopic geometric drivers dominate the bulk flow at the fundamental cardiac frequency, they are subject to significant inertial damping as the harmonic frequency increases. In contrast, the anisotropy-induced Lamb vector, sustained by the sharp gradients of the oscillatory boundary layer, evades this macroscopic attenuation. These findings define a geometry-independent baseline for multidirectional pulsatile dynamics and provide a theoretical basis for future spectral investigations of endothelial mechanobiology under high-frequency, near-wall inertial stimuli. © The Author(s) 2026.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2026-a-transverse-piconewton-force-revealed-in-anisotro"
},
{
"id": "scopus-2026-resonant-spectral-cascade-in-womersley-flow-trigge",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr2026",
"entry_type": "article",
"title": "Resonant spectral cascade in Womersley flow triggered by arterial geometry",
"year": 2026,
"venue": "Physics of Fluids",
"volume": "38",
"issue": "4",
"pages": "",
"doi": "10.1063/5.0319995",
"doi_url": "https://doi.org/10.1063/5.0319995",
"scopus_url": "https://www.scopus.com/pages/publications/105035588677?origin=resultslist",
"authors": "Saqr, Khalid M.",
"abstract": "Age-related arterial remodeling is dominated by progressive loss of elastic-fiber function and concomitant stiffening, and in many vascular beds, it is also accompanied by measurable geometric remodeling (e.g., elongation and tortuosity). These changes are clinically relevant because they modify pulsatile phase relationships, near-wall shear, and axial transport, yet the precise physical mechanisms by which geometry modulates spectral energy redistribution remain insufficiently resolved. While complex geometry is known to increase viscous resistance, its active role in modulating flow dynamics is not fully understood. Here, we solve a mathematical model to show that arterial geometry can trigger a resonant transfer of energy to short-wavelength components of the flow. The investigation, conducted over a physiological range of Womersley numbers (Wo, a dimensionless measure of pulsation frequency), reveals a dual dynamic. The global wave energy consistently decays, confirmed by a negative growth rate (G < 0), indicating that the flow does not become exponentially unstable. However, a spectral broadening ratio (R), which quantifies the energy in high-wavenumber vs low-wavenumber modes, exhibits a sharp, non-monotonic peak at an intermediate Wo. This result identifies a resonant frequency at which geometry is maximally efficient at generating spectral complexity, even as the overall flow attenuates. These findings reframe the role of arterial geometry from a passive dissipator to an active modulator of the flow's spectral content, suggesting that spectral diagnostics could provide a sensitive marker for vascular health. © 2026 Author(s).",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2026-resonant-spectral-cascade-in-womersley-flow-trigge"
},
{
"id": "scopus-2025-effects-of-wall-compliance-on-pulsatile-flow-in-a-",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Yamaguchi2025",
"entry_type": "article",
"title": "Effects of wall compliance on pulsatile flow in a full-scale, patient-specific cerebral aneurysm model: Particle image velocimetry experiments",
"year": 2025,
"venue": "Medical Engineering and Physics",
"volume": "142",
"issue": "",
"pages": "",
"doi": "10.1016/j.medengphy.2025.104381",
"doi_url": "https://doi.org/10.1016/j.medengphy.2025.104381",
"scopus_url": "https://www.scopus.com/pages/publications/105008214100?origin=resultslist",
"authors": "Yamaguchi, Ryuhei and Albadawi, Muhamed and Shafii, Nadia Shaira and Saito, Atsushi and Nakata, Toshiyuki and Saqr, Khalid M. and Anzai, Hitomi and Ohta, Makoto",
"abstract": "The hemodynamics of elastic cerebral aneurysms are complicated by phenomena that affect the initiation and the progress of each aneurysm. The blood vessel deforms with pulsatile flow. In a phantom, however, it remains unclear whether the wall compliance can be neglected. In our previous study, the flow structure at another plane oriented perpendicular to the median plane was not clarified. In the approach presented here, an identical phantom is used for both the rigid and elastic wall models by adjusting the surrounding fluid when immersed in a bath. For this purpose, the full-scale phantom of an aneurysm was fabricated using a silicone elastomer. The hemodynamic factors at the orthogonal planes in the non-deformable and deformable models of the bifurcation in the middle cerebral artery were examined. Using two-dimensional particle image velocimetry, the flow velocity, the wall shear stress (WSS), the WSS gradient (WSSG), and the turbulent kinetic energy (TKE) were measured during pulsatile flow. Overall, the WSSG at the median plane is smaller than that at corresponding perpendicular plane. Additionally, the TKE in the deformable model is smaller than that in the non-deformable model. Our results have clarified the complex effects of aneurysm wall compliance on these hemodynamic factors. © 2025",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2025-effects-of-wall-compliance-on-pulsatile-flow-in-a-"
},
{
"id": "scopus-2025-judicial-authority-and-rhetorical-strategies-in-eg",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Elyamany20252419",
"entry_type": "article",
"title": "Judicial Authority and Rhetorical Strategies in Egyptian Abortion Rulings: A Computational Forensic Analysis",
"year": 2025,
"venue": "International Journal for the Semiotics of Law",
"volume": "38",
"issue": "7",
"pages": "2419 - 2443",
"doi": "10.1007/s11196-025-10300-0",
"doi_url": "https://doi.org/10.1007/s11196-025-10300-0",
"scopus_url": "https://www.scopus.com/pages/publications/105007886037?origin=resultslist",
"authors": "Elyamany, Nashwa and Abbas, Noorhan and Saqr, Khalid M.",
"abstract": "This study employs a computational forensic linguistic framework to examine how the Egyptian Court of Cassation discursively and semiotically constructs judicial authority in abortion rulings amid tensions between statutory criminalization, Islamic jurisprudence, and international human rights norms. Analyzing 200 Court of Cassation decisions (1990–2023) through Natural Language Processing (NLP), Frame Semantics, and Appraisal Theory, the paper uncovers a strategic interplay of legal, religious, and rhetorical strategies. The research identifies prevailing trends such as the dominant use of doctrinal modification and a marked absence of religious or international legal discourse while also uncovering interpretive divergences that reveal the flexible and pragmatic character of Egyptian jurisprudence. Through close reading and semiotic analysis, the study shows how courts selectively affirm precedent, introduce forensic evidence to modulate legal culpability, and strategically omit religious justification, thereby signaling a shift toward legal secularization. Medical semiotics and procedural nuances serve as symbolic resources that allow courts to navigate moral ambiguity without openly contradicting established doctrine. This discursive economy reflects a hybrid legal model: stable in its symbolic invocation of precedent, yet dynamic in practice. The findings contribute to scholarship on legal semiotics, reproductive governance, and the evolving role of judicial discourse in negotiating state, science, and religion in contemporary Egypt. By integrating computational methods with critical discourse analysis, this study advances Arabic legal NLP and illustrates how hybrid legal systems strategically navigate plural normative orders. © The Author(s) 2025.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2025-judicial-authority-and-rhetorical-strategies-in-eg"
},
{
"id": "scopus-2022-characteristic-effect-of-wall-elasticity-on-flow-i",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Yamaguchi2022",
"entry_type": "article",
"title": "Characteristic effect of wall elasticity on flow instability and wall shear stress of a full-scale, patient-specific aneurysm model in the middle cerebral artery: An experimental approach",
"year": 2022,
"venue": "Journal of Applied Physics",
"volume": "131",
"issue": "18",
"pages": "",
"doi": "10.1063/5.0085417",
"doi_url": "https://doi.org/10.1063/5.0085417",
"scopus_url": "https://www.scopus.com/pages/publications/85130286764?origin=resultslist",
"authors": "Yamaguchi, Ryuhei and Tanaka, Gaku and Shafii, Nadia Shaira and Osman, Kahar and Shimizu, Yasutomo and Saqr, Khalid M. and Ohta, Makoto",
"abstract": "The mechanisms underlying the growth and rupture of aneurysms are poorly understood. Although the wall shear stress (WSS) in elastic aneurysm models is examined using fluid-structure interaction (FSI) simulations, it has not been sufficiently validated using experimental modalities, such as particle image velocimetry (PIV) or phase contrast magnetic resonance imaging (PC-MRI). In this study, we investigated pulsatile flow in an elastic, image-based, patient-specific cerebral aneurysm model using PIV. The phantom model was carefully fabricated using a specialized technique by silicone elastomer. We explored the hemodynamics of the WSS and the kinetic energy cascade (KEC) in the elastic model compared with a rigid model, at the apex of the bifurcation of the middle cerebral artery (MCA) in vitro. The effects of elasticity on the WSS, WSS gradient (WSSG), and tensile strength of the aneurysm wall were also investigated, in addition to the effect of wall elasticity on the KEC compared to a rigid wall. Although the WSSG around the stagnation point had a large positive value, there was no difference between the two models. In particular, wall elasticity suppressed the WSS magnitude around the stagnation point and attenuated the KEC (i.e., the flow fluctuation). Future studies examining KEC frequency and WSS characteristics in a phantom model should consider assessing elasticity. © 2022 Author(s).",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2022-characteristic-effect-of-wall-elasticity-on-flow-i"
},
{
"id": "scopus-2022-influence-of-bone-marrow-characteristic-and-trabec",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Rabiatul20221682",
"entry_type": "article",
"title": "Influence of bone marrow characteristic and trabecular bone morphology on bone remodelling process with FSI approach",
"year": 2022,
"venue": "Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications",
"volume": "236",
"issue": "8",
"pages": "1682 - 1695",
"doi": "10.1177/14644207221080115",
"doi_url": "https://doi.org/10.1177/14644207221080115",
"scopus_url": "https://www.scopus.com/pages/publications/85125525290?origin=resultslist",
"authors": "Rabiatul, A.A.R. and Rianti, Devi and Fatihhi, S.J. and Md Saad, Amir Putra and Zakaria, Zulfadzli and Yuliati, Anita and Harun, M.N. and Kadir, M.R.A. and Öchsner, Andreas and Kamarul, Tunku and Saqr, Khalid M and Syahrom, Ardiyansyah",
"abstract": "While doing daily physiological activities, the trabecular bone will experience a certain amount of deformation which leads to the bone marrow movement. The movement can affect the bone remodelling process and the properties of the bone itself. The bone marrow plays a role as a hydraulic stiffening of the trabecular structure. However, previous studies analysed on trabecular bone and bone marrow separately, which is not considered as the actual condition. Thus, it is crucial to consider combine analyses of the bone marrow with the trabecular structure simultaneous. The aim of this study is to investigate the effect of bone marrow on the mechanical environment and the structure of trabecular bone during normal walking loading. Hence, this study used the Fluid-Structure Interaction (FSI) approach as a finite element method to discover the effect of bone marrow to the trabecular structure and vice versa. The findings show the shear stress value along normal walking phase was found in a range of 0.01–0.27 Pa which is sufficient to regulated cell response minimally. This study provides insight into understanding the related mechanobiological responds towards supply of nutrients onto bone cells. © IMechE 2022.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2022-influence-of-bone-marrow-characteristic-and-trabec"
},
{
"id": "scopus-2022-non-kolmogorov-turbulence-in-carotid-artery-stenos",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr2022",
"entry_type": "article",
"title": "Non-Kolmogorov turbulence in carotid artery stenosis and the impact of carotid stenting on near-wall turbulence",
"year": 2022,
"venue": "AIP Advances",
"volume": "12",
"issue": "1",
"pages": "",
"doi": "10.1063/5.0076271",
"doi_url": "https://doi.org/10.1063/5.0076271",
"scopus_url": "https://www.scopus.com/pages/publications/85123776815?origin=resultslist",
"authors": "Saqr, Khalid M. and Kano, Kiyomitsu and Rashad, Sherif and Niizuma, Kuniyasu and Kaku, Yasuhiko and Iwama, Toru and Tominaga, Teiji",
"abstract": "Endovascular stents have become a standard management procedure for carotid artery stenosis. Recent discoveries related to the complex turbulence dynamics in blood flow necessitate revisiting the pathology of carotid stenosis itself and the impact of stenting on blood hemodynamics. In the present work, and for the first time, the therapeutic hemodynamic changes after carotid artery stenting are explored via high-resolution large eddy simulation of non-Newtonian multiharmonic pulsatile flow in realistic patient-specific geometries. The focus of the present study is the transition to turbulence before and after stent deployment. Transition to turbulence was characterized in space, time, and frequency domains. The multiharmonic flow had generalized a time-dependent Reynolds number of 115 ± 26 at the inlet plane of the computational domain. The inlet boundary condition was defined as a multiharmonic waveform represented by six harmonics that are responsible for transferring at least 94% of the mass flow rate in the common carotid artery. Multiharmonic non-Newtonian pulsatile flow exhibited non-Kolmogorov turbulence characteristics. The stent was found to cause a significant reduction in the velocity oscillations downstream the stenosis throat and restore the inverse kinetic energy cascade. It also stabilized hemorheological fluctuations downstream the stenosis throat. Finally, the stent had a significant effect on the kinetic energy cascade at a distance of 10 μm from the artery wall at the carotid bifurcation and stenosis throat. These findings are important to guide the design and optimization of carotid stents and have significant value in understanding the mechanisms of vascular remodeling and carotid stenosis pathophysiology and symptomatology. © 2022 Author(s).",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2022-non-kolmogorov-turbulence-in-carotid-artery-stenos"
},
{
"id": "scopus-2022-on-non-kolmogorov-turbulence-in-blood-flow-and-its",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr2022",
"entry_type": "article",
"title": "On non-Kolmogorov turbulence in blood flow and its possible role in mechanobiological stimulation",
"year": 2022,
"venue": "Scientific Reports",
"volume": "12",
"issue": "1",
"pages": "",
"doi": "10.1038/s41598-022-16079-5",
"doi_url": "https://doi.org/10.1038/s41598-022-16079-5",
"scopus_url": "https://www.scopus.com/pages/publications/85135267892?origin=resultslist",
"authors": "Saqr, Khalid M. and Zidane, Iham F.",
"abstract": "The study of turbulence in physiologic blood flow is important due to its strong relevance to endothelial mechanobiology and vascular disease. Recently, Saqr et al. (Sci Rep 10, 15,492, 2020) discovered non-Kolmogorov turbulence in physiologic blood flow in vivo, traced its origins to the Navier–Stokes equation and demonstrated some of its properties using chaos and hydrodynamic-stability theories. The present work extends these findings and investigates some inherent characteristics of non-Kolmogorov turbulence in monoharmonic and multiharmonic pulsatile flow under ideal physiologic conditions. The purpose of this work is to propose a conjecture for the origins for picoNewton forces that are known to regulate endothelial cells’ functions. The new conjecture relates these forces to physiologic momentum-viscous interactions in the near-wall region of the flow. Here, we used high-resolution large eddy simulation (HRLES) to study pulsatile incompressible flow in a straight pipe of L/ D= 20. The simulations presented Newtonian and Carreau–Yasuda fluid flows, at Rem≈ 250 , each represented by one, two and three boundary harmonics. Comparison was established based on maintaining constant time-averaged mass flow rate in all simulations. First, we report the effect of primary harmonics on the global power budget using primitive variables in phase space. Second, we describe the non-Kolmogorov turbulence in frequency domain. Third, we investigate the near-wall coherent structures in time and space domains. Finally, we propose a new conjecture for the role of turbulence in endothelial cells’ mechanobiology. The proposed conjecture correlates near-wall turbulence to a force field of picoNewton scale, suggesting possible relevance to endothelial cells mechanobiology. © 2022, The Author(s).",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2022-on-non-kolmogorov-turbulence-in-blood-flow-and-its"
},
{
"id": "scopus-2021-numerical-study-on-the-energy-cascade-of-pulsatile",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Mahrous2021",
"entry_type": "article",
"title": "Numerical study on the energy cascade of pulsatile Newtonian and power-law flow models in an ICA bifurcation",
"year": 2021,
"venue": "PLoS ONE",
"volume": "16",
"issue": "1 January",
"pages": "",
"doi": "10.1371/journal.pone.0245775",
"doi_url": "https://doi.org/10.1371/journal.pone.0245775",
"scopus_url": "https://www.scopus.com/pages/publications/85100390540?origin=resultslist",
"authors": "Mahrous, Samar A. and Che Sidik, Nor Azwadi and Saqr, Khalid M.",
"abstract": "The complex physics and biology underlying intracranial hemodynamics are yet to be fully revealed. A fully resolved direct numerical simulation (DNS) study has been performed to identify the intrinsic flow dynamics in an idealized carotid bifurcation model. To shed the light on the significance of considering blood shear-thinning properties, the power-law model is compared to the commonly used Newtonian viscosity hypothesis. We scrutinize the kinetic energy cascade (KEC) rates in the Fourier domain and the vortex structure of both fluid models and examine the impact of the power-law viscosity model. The flow intrinsically contains coherent structures which has frequencies corresponding to the boundary frequency, which could be associated with the regulation of endothelial cells. From the proposed comparative study, it is found that KEC rates and the vortex-identification are significantly influenced by the shear-thinning blood properties. Conclusively, from the obtained results, it is found that neglecting the non-Newtonian behavior could lead to underestimation of the hemodynamic parameters at low Reynolds number and overestimation of the hemodynamic parameters by increasing the Reynolds number. In addition, we provide physical insight and discussion onto the hemodynamics associated with endothelial dysfunction which plays significant role in the pathogenesis of intracranial aneurysms. Copyright: © 2021 Mahrous et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2021-numerical-study-on-the-energy-cascade-of-pulsatile"
},
{
"id": "scopus-2020-author-correction-the-hemodynamic-complexities-und",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Rashad2020",
"entry_type": "article",
"title": "Author Correction: The hemodynamic complexities underlying transient ischemic attacks in early-stage Moyamoya disease: an exploratory CFD study (Scientific Reports, (2020), 10, 1, (3700), 10.1038/s41598-020-60683-2)",
"year": 2020,
"venue": "Scientific Reports",
"volume": "10",
"issue": "1",
"pages": "",
"doi": "10.1038/s41598-020-62862-7",
"doi_url": "https://doi.org/10.1038/s41598-020-62862-7",
"scopus_url": "https://www.scopus.com/pages/publications/85083051249?origin=resultslist",
"authors": "Rashad, Sherif and Saqr, Khalid M. and Fujimura, Miki and Niizuma, Kuniyasu and Tominaga, Teiji",
"abstract": "An amendment to this paper has been published and can be accessed via a link at the top of the paper. © 2020, The Author(s).",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2020-author-correction-the-hemodynamic-complexities-und"
},
{
"id": "scopus-2020-computational-fluid-dynamics-simulations-of-cerebr",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr2020711",
"entry_type": "article",
"title": "Computational fluid dynamics simulations of cerebral aneurysm using Newtonian, power-law and quasi-mechanistic blood viscosity models",
"year": 2020,
"venue": "Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine",
"volume": "234",
"issue": "7",
"pages": "711 - 719",
"doi": "10.1177/0954411920917531",
"doi_url": "https://doi.org/10.1177/0954411920917531",
"scopus_url": "https://www.scopus.com/pages/publications/85084996952?origin=resultslist",
"authors": "Saqr, Khalid M",
"abstract": "Cerebral aneurysm is a fatal neurovascular disorder. Computational fluid dynamics simulation of aneurysm haemodynamics is one of the most important research tools which provide increasing potential for clinical applications. However, computational fluid dynamics modelling of such delicate neurovascular disorder involves physical complexities that cannot be easily simplified. Recently, it was shown that the Newtonian simplification used to close the shear stress tensor of the Navier–Stokes equation is not sufficient to explore aneurysm haemodynamics. This article explores the differences between the latter simplification, non-Newtonian power-law model and a newly proposed quasi-mechanistic model. The modified Krieger model, which treats blood as a suspension of plasma and particles, was implemented in computational fluid dynamics context here for the first time and is made available to the readers in a C# code in the supplementary material of this article. Two middle-cerebral artery and two anterior-communicating artery aneurysms, all ruptured, were utilized here as case studies. It was shown that the modified Krieger model had higher sensitivity for wall shear stress calculations in comparison with the other two models. The modified Krieger model yielded lower wall shear stress values consistently in comparison with the other two models. Moreover, the modified Krieger model has generally predicted higher pressure in the aneurysm models. Based on published aneurysm rupture studies, it is believed that ruptured aneurysms are usually correlated with lower wall shear stress values than unruptured ones. Therefore, this work concludes that the modified Krieger model is a potential candidate for providing better clinical relevance to aneurysm computational fluid dynamics simulations. © IMechE 2020.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2020-computational-fluid-dynamics-simulations-of-cerebr"
},
{
"id": "scopus-2020-effects-of-wall-compliance-on-multiharmonic-pulsat",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Tupin2020",
"entry_type": "article",
"title": "Effects of wall compliance on multiharmonic pulsatile flow in idealized cerebral aneurysm models: comparative PIV experiments",
"year": 2020,
"venue": "Experiments in Fluids",
"volume": "61",
"issue": "7",
"pages": "",
"doi": "10.1007/s00348-020-02998-4",
"doi_url": "https://doi.org/10.1007/s00348-020-02998-4",
"scopus_url": "https://www.scopus.com/pages/publications/85087103579?origin=resultslist",
"authors": "Tupin, Simon and Saqr, Khalid M. and Ohta, Makoto",
"abstract": "Abstract: The hemodynamics of intracranial aneurysm (IA) comprise complex phenomena that influence the IA’s growth and rupture risk. It has long been argued in in silico studies of IA hemodynamics that wall compliance could be neglected, because it does not alter the hemodynamic patterns. The purpose of this work is to investigate the effect of wall compliance on IA hemodynamic patterns and flow field variables. We conducted comparative in vitro laser PIV measurements on rigid silicone and elastic PVA-H models of side-wall IA. In the first study of its kind, the interaction between wall dynamics and IA hemodynamics is investigated experimentally at high spatio-temporal resolution. It is evidently shown that wall compliance affects the phase-shift, flow rate and pressure damping, velocity and vorticity fields inside the aneurysm in space and time. Near-wall velocity field, which affects vascular endothelial cells in reality, was found to have larger oscillations in the compliant model, leading to higher turbulent kinetic energy. Wall shear stress was also affected by wall compliance, with lower time average values but larger temporal variations. These differences emphasize the importance of modeling the compliance behavior of cerebral arteries in the study of aneurysms and their treatment. Graphic abstract: [Figure not available: see fulltext.] © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2020-effects-of-wall-compliance-on-multiharmonic-pulsat"
},
{
"id": "scopus-2020-epigenetic-response-of-endothelial-cells-to-differ",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Rashad20207827",
"entry_type": "article",
"title": "Epigenetic response of endothelial cells to different wall shear stress magnitudes: A report of new mechano-miRNAs",
"year": 2020,
"venue": "Journal of Cellular Physiology",
"volume": "235",
"issue": "11",
"pages": "7827 - 7839",
"doi": "10.1002/jcp.29436",
"doi_url": "https://doi.org/10.1002/jcp.29436",
"scopus_url": "https://www.scopus.com/pages/publications/85077840479?origin=resultslist",
"authors": "Rashad, Sherif and Han, Xiaobo and Saqr, Khalid and Tupin, Simon and Ohta, Makoto and Niizuma, Kuniyasu and Tominaga, Teiji",
"abstract": "Endothelial cells (ECs) respond to flow stress via a variety of mechanisms, leading to various intracellular responses that can modulate the vessel wall and lead to diseases if the flow is disturbed. Mechano-microRNAs (miRNAs) are a subset of miRNAs in the ECs that are flow responsive. Mechano-miRNAs were shown to be related to atherosclerosis pathophysiology, and a number of them were identified as pathologic. Here, we exposed human carotid ECs to different wall shear stresses (WSS), high and low, and evaluated the response of miRNAs by microarray and quantitative polymerase chain reaction analysis. We discovered five new mechano-miRNAs that were not reported in that context previously to the best of our knowledge. Moreover, functional pathway analysis revealed that under low WSS conditions, several pathways regulating apoptosis are affected. In addition, KLF2 and KLF4, known atheroprotective genes, were downregulated under low WSS and upregulated under high WSS. KLF2 and VCAM1, both angiogenic, were upregulated under high WSS. NOS3, which is vascular protective, was also upregulated with higher WSS. On the contrary, ICAM-1 and E-selectin, both atherogenic and proinflammatory, were upregulated with high WSS. Collectively, the epigenetic landscape with the gene expression analysis reveals that low WSS is associated with a proapoptotic state, while high WSS is associated with a proliferative and proinflammatory state. © 2020 Wiley Periodicals, Inc.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2020-epigenetic-response-of-endothelial-cells-to-differ"
},
{
"id": "scopus-2020-exergy-analysis-of-large-and-impounded-hydropower-",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Abuelnuor2020",
"entry_type": "article",
"title": "Exergy analysis of large and impounded hydropower plants: Case study El Roseires Dam (280 MW)",
"year": 2020,
"venue": "Environmental Progress and Sustainable Energy",
"volume": "39",
"issue": "3",
"pages": "",
"doi": "10.1002/ep.13362",
"doi_url": "https://doi.org/10.1002/ep.13362",
"scopus_url": "https://www.scopus.com/pages/publications/85074774552?origin=resultslist",
"authors": "Abuelnuor, Abuelnuor A. A. and Ahmed, Khadir and Saqr, Khaled M. and Nogoud, Yasser A. M. and Babiker, Mohammed E. A. M.",
"abstract": "Nowadays, one of the major and serious worldly concerns is the limitation of energy resources. Sudan, in specific, confronts a critical crisis in fossil fuel resources due to its separation science 2011, and mostly concerning the production of electricity energy. There are many sources of renewable energies in Sudan such as hydropower. Which it is widely used in Sudan, and one example is Elroseires hydropower plant. This research aims to conduct an exergy analysis of the performance of the Elroseires hydropower plant to identify areas for improvement using actual operation data. The exergy efficiency and exergy destruction rate of each unit in the plant were determined independently. The thermodynamic inefficiencies of all units of the plant were quantified for analysis to identify breakthrough points for further energy savings. Results indicated that the lowest exergy destruction rate occurs in August (20.6 MW) despite the lowest production of energy during this period. This outcome is due to the volumetric flow rate being less than those in other months, thereby leading to minimal flow turbulence that result in low exergy destruction. By contrast, the greatest exergy destruction occurs in December (106.1 MW) because of the high volumetric flow rate for the same pipe diameter. Such condition leads to turbulent flow and results in considerable exergy destruction. This study emphasizes that exergy analysis is useful in determining irreversibilities and losses in Elroseires hydropower plant to improve its thermodynamic performance. © 2019 American Institute of Chemical Engineers",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2020-exergy-analysis-of-large-and-impounded-hydropower-"
},
{
"id": "scopus-2020-investigation-of-newtonian-and-power-law-blood-flo",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Mahrous2020148",
"entry_type": "article",
"title": "Investigation of newtonian and power-law blood flow models in a 180° curved pipe at low to medium shear rate",
"year": 2020,
"venue": "Journal of Advanced Research in Fluid Mechanics and Thermal Sciences",
"volume": "69",
"issue": "1",
"pages": "148 - 162",
"doi": "10.37934/arfmts.69.1.148162",
"doi_url": "https://doi.org/10.37934/arfmts.69.1.148162",
"scopus_url": "https://www.scopus.com/pages/publications/85087088876?origin=resultslist",
"authors": "Mahrous, Samar Ahmed and Sidik, Nor Azwadi Che and Saqr, Khalid Mansour",
"abstract": "The purpose of this brief paper is to obtain quantitative information on mean velocity profile in ideal vasculature (i.e. straight and toroidal pipes) at low to medium shear rates. To shed the light on the significance of considering blood shear-thinning properties, the power-law model is compared to the commonly used Newtonian viscosity hypothesis. Validated CFD models of blood flow were established and parameterized to solve steady incompressible blood flow under Reynolds number of 50~200. The calculations of the Reynolds number and boundary conditions adopted the shear-thinning index of the power-law models to provide physically correct benchmark for the comparison presented herein. Velocity profiles for Newtonian and non-Newtonian fluid flow are described and sketched. Shear rate values had a range of 20~200 s-1 which represents the physiological range found in cerebral vasculature. This study provides the means to estimate the effect of the non-Newtonian properties of the blood on the flow patterns. It is clearly shown that the difference between Newtonian and power-law blood flow models is not significantly affected by Reynolds number for the current range of shear rate. The differences identified in the pressuredrop per unit length and average wall-shear stress were found to be of significant values. The difference between the Newtonian and power-law model (case1) in the pressure drop per unit length for the straight pipe was 386 while for the curved pipe was 371. These differences increased to 538 at Re=200 for the straight pipe and reached 603 for the curved pipe. This research suggests that the non-Newtonian effects of cerebral blood flow should be considered in the respective CFD models. © 2020 PENERBIT AKADEMIA BARU.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2020-investigation-of-newtonian-and-power-law-blood-flo"
},
{
"id": "scopus-2020-newtonian-and-non-newtonian-cfd-models-of-intracra",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Mahrous202062",
"entry_type": "article",
"title": "Newtonian and non-newtonian CFD models of intracranial aneurysm: A review",
"year": 2020,
"venue": "CFD Letters",
"volume": "12",
"issue": "1",
"pages": "62 - 86",
"doi": "",
"doi_url": "",
"scopus_url": "https://www.scopus.com/pages/publications/85084170689?origin=resultslist",
"authors": "Mahrous, Samar A. and Sidik, Nor Azwadi Che and Saqr, Khalid M.",
"abstract": "Computational Fluid Dynamics (CFD) has become an essential research tool to investigate the physical, biophysical and pathophysiological processes leading to the formation, growth and rupture of intracranial aneurysms (IAs). The diverse anatomical complexities of IAs dictate a staggering level of sophistication inherited in the CFD modeling process. From medical imaging to wall shear stress mapping on the aneurysm walls, there are numerous physical assumptions related to blood flow and wall dynamics. The majority of such assumptions remain controversial until today. This review is an endeavor to summarize, in a critical and comprehensive manner, the different assumptions used to calculate blood viscosity in CFD models of IA hemodynamics. The tabulated summaries of literature presented herein also highlight the inconsistency of location choice and imaging techniques used to select IA models for CFD studies. This review presents a roadmap for the state-of-the art knowledge about blood viscosity models used with IA CFD models, and suggests future research directions to further characterize the nature of blood flow which contributes to the improvement of diagnosis and management of IAs. © 2020 PENERBIT AKADEMIA BARU-All rights reserved.",
"publication_stage": "Final",
"public": true,
"evidence_level": "scopus-record-no-doi",
"record_id": "scopus-2020-newtonian-and-non-newtonian-cfd-models-of-intracra"
},
{
"id": "scopus-2020-performance-of-a-wind-turbine-blade-in-sandstorms-",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Zidane2020",
"entry_type": "article",
"title": "Performance of a wind turbine blade in sandstorms using a CFD-BEM based neural network",
"year": 2020,
"venue": "Journal of Renewable and Sustainable Energy",
"volume": "12",
"issue": "5",
"pages": "",
"doi": "10.1063/5.0012272",
"doi_url": "https://doi.org/10.1063/5.0012272",
"scopus_url": "https://www.scopus.com/pages/publications/85094903598?origin=resultslist",
"authors": "Zidane, Iham F. and Swadener, Greg and Ma, Xianghong and Shehadeh, Mohamed F. and Salem, Mahmoud H. and Saqr, Khalid M.",
"abstract": "In arid regions, such as the North African desert, sandstorms impose considerable restrictions on horizontal axis wind turbines (HAWTs), which have not been thoroughly investigated. This paper examines the effects of debris flow on the power generation of the HAWT. Computational Fluid Dynamics (CFD) models were established and validated to provide novel insight into the effects of debris on the aerodynamic characteristics of NACA 63415. To account for the change in the chord length and Reynolds number along the span of the blade and the 3D flow patterns, the power curves for a wind turbine were obtained using the Blade Element Momentum (BEM) method. We present a novel coupled application of the neural network, CFD, and BEM to investigate the erosion rates of the blade due to different sandstorm conditions. The proposed model can be scaled and developed to assist in monitoring and prediction of HAWT blade conditions. This work shows that HAWT performance can be significantly diminished due to the aerodynamic losses under sandstorm conditions. The power generated under debris flow conditions can decrease from 10 to 30% compared to clean conditions. © 2020 Author(s).",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2020-performance-of-a-wind-turbine-blade-in-sandstorms-"
},
{
"id": "scopus-2020-physiologic-blood-flow-is-turbulent",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr2020",
"entry_type": "article",
"title": "Physiologic blood flow is turbulent",
"year": 2020,
"venue": "Scientific Reports",
"volume": "10",
"issue": "1",
"pages": "",
"doi": "10.1038/s41598-020-72309-8",
"doi_url": "https://doi.org/10.1038/s41598-020-72309-8",
"scopus_url": "https://www.scopus.com/pages/publications/85091426040?origin=resultslist",
"authors": "Saqr, Khalid M. and Tupin, Simon and Rashad, Sherif and Endo, Toshiki and Niizuma, Kuniyasu and Tominaga, Teiji and Ohta, Makoto",
"abstract": "Contemporary paradigm of peripheral and intracranial vascular hemodynamics considers physiologic blood flow to be laminar. Transition to turbulence is considered as a driving factor for numerous diseases such as atherosclerosis, stenosis and aneurysm. Recently, turbulent flow patterns were detected in intracranial aneurysm at Reynolds number below 400 both in vitro and in silico. Blood flow is multiharmonic with considerable frequency spectra and its transition to turbulence cannot be characterized by the current transition theory of monoharmonic pulsatile flow. Thus, we decided to explore the origins of such long-standing assumption of physiologic blood flow laminarity. Here, we hypothesize that the inherited dynamics of blood flow in main arteries dictate the existence of turbulence in physiologic conditions. To illustrate our hypothesis, we have used methods and tools from chaos theory, hydrodynamic stability theory and fluid dynamics to explore the existence of turbulence in physiologic blood flow. Our investigation shows that blood flow, both as described by the Navier–Stokes equation and in vivo, exhibits three major characteristics of turbulence. Womersley’s exact solution of the Navier–Stokes equation has been used with the flow waveforms from HaeMod database, to offer reproducible evidence for our findings, as well as evidence from Doppler ultrasound measurements from healthy volunteers who are some of the authors. We evidently show that physiologic blood flow is: (1) sensitive to initial conditions, (2) in global hydrodynamic instability and (3) undergoes kinetic energy cascade of non-Kolmogorov type. We propose a novel modification of the theory of vascular hemodynamics that calls for rethinking the hemodynamic–biologic links that govern physiologic and pathologic processes. © 2020, The Author(s).",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2020-physiologic-blood-flow-is-turbulent"
},
{
"id": "scopus-2020-the-hemodynamic-complexities-underlying-transient-",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Rashad2020",
"entry_type": "article",
"title": "The hemodynamic complexities underlying transient ischemic attacks in early-stage Moyamoya disease: an exploratory CFD study",
"year": 2020,
"venue": "Scientific Reports",
"volume": "10",
"issue": "1",
"pages": "",
"doi": "10.1038/s41598-020-60683-2",
"doi_url": "https://doi.org/10.1038/s41598-020-60683-2",
"scopus_url": "https://www.scopus.com/pages/publications/85080839553?origin=resultslist",
"authors": "Rashad, Sherif and Saqr, Khalid M. and Fujimura, Miki and Niizuma, Kuniyasu and Tominaga, Teiji",
"abstract": "Moyamoya disease (MMD) is a rare cerebro-occlusive disease with unknown etiology that can cause both ischemic and hemorrhagic stroke. MMD is characterized by progressive stenosis of the terminal internal carotid artery (ICA) and development of basal brain collaterals. Early-stage MMD is known to cause hemodynamic insufficiency despite mild or moderate stenosis of the intracranial arteries, but the exact mechanism underlying this pathophysiological condition is undetermined. We used high-resolution Large Eddy Simulations to investigate multiple complex hemodynamic phenomena that led to cerebral ischemia in five patients with early-stage MMD. The effects of transitional flow, coherent flow structures and blood shear-thinning properties through regions of tortuous and stenosed arteries were explored and linked to symptomatology. It is evidently shown that in some cases complex vortex structures, such as Rankine-type vortices, redirects blood flow away from some arteries causing significant reduction in blood flow. Moreover, partial blood hammer (PBH) phenomenon was detected in some cases and led to significant hemodynamic insufficiency. PBH events were attributed to the interaction between shear-thinning properties, transitional flow structures and loss of upstream pressure-velocity phase lag. We clearly show that the hemodynamic complexities in early-stage MMD could induce ischemia and explain the non-responsiveness to antiplatelet therapy. © 2020, The Author(s).",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2020-the-hemodynamic-complexities-underlying-transient-"
},
{
"id": "scopus-2020-what-does-computational-fluid-dynamics-tell-us-abo",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr20201021",
"entry_type": "article",
"title": "What does computational fluid dynamics tell us about intracranial aneurysms? A meta-analysis and critical review",
"year": 2020,
"venue": "Journal of Cerebral Blood Flow and Metabolism",
"volume": "40",
"issue": "5",
"pages": "1021 - 1039",
"doi": "10.1177/0271678x19854640",
"doi_url": "https://doi.org/10.1177/0271678x19854640",
"scopus_url": "https://www.scopus.com/pages/publications/85068191487?origin=resultslist",
"authors": "Saqr, Khalid M and Rashad, Sherif and Tupin, Simon and Niizuma, Kuniyasu and Hassan, Tamer and Tominaga, Teiji and Ohta, Makoto",
"abstract": "Despite the plethora of published studies on intracranial aneurysms (IAs) hemodynamic using computational fluid dynamics (CFD), limited progress has been made towards understanding the complex physics and biology underlying IA pathophysiology. Guided by 1733 published papers, we review and discuss the contemporary IA hemodynamics paradigm established through two decades of IA CFD simulations. We have traced the historical origins of simplified CFD models which impede the progress of comprehending IA pathology. We also delve into the debate concerning the Newtonian fluid assumption used to represent blood flow computationally. We evidently demonstrate that the Newtonian assumption, used in almost 90% of studies, might be insufficient to describe IA hemodynamics. In addition, some fundamental properties of the Navier–Stokes equation are revisited in supplementary material to highlight some widely spread misconceptions regarding wall shear stress (WSS) and its derivatives. Conclusively, our study draws a roadmap for next-generation IA CFD models to help researchers investigate the pathophysiology of IAs. © The Author(s) 2019.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2020-what-does-computational-fluid-dynamics-tell-us-abo"
},
{
"id": "scopus-2019-evidence-for-non-newtonian-behavior-of-intracrania",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr20191029",
"entry_type": "article",
"title": "Evidence for non-Newtonian behavior of intracranial blood flow from Doppler ultrasonography measurements",
"year": 2019,
"venue": "Medical and Biological Engineering and Computing",
"volume": "57",
"issue": "5",
"pages": "1029 - 1036",
"doi": "10.1007/s11517-018-1926-9",
"doi_url": "https://doi.org/10.1007/s11517-018-1926-9",
"scopus_url": "https://www.scopus.com/pages/publications/85058119744?origin=resultslist",
"authors": "Saqr, Khalid M. and Mansour, Ossama and Tupin, Simon and Hassan, Tamer and Ohta, Makoto",
"abstract": "Computational fluid dynamics (CFD) studies of intracranial hemodynamics often use Newtonian viscosity model to close the shear rate term in the Navier-Stokes equation. This is based on a commonly accepted hypothesis which state that non-Newtonian effects can be neglected in intracranial blood flow. This study aims to examine the validity of such hypothesis to guide future CFD studies of intracranial hemodynamics. Doppler ultrasonography (DUS) measurements of systolic and diastolic vessel diameter and blood velocity were conducted on 16 subjects (mean age 50.6). The measurements were conducted on the internal carotid (ICA), middle cerebral (MCA), and anterior communicating (AComA) arteries. Systolic and diastolic wall shear stress (WSS) values were calculated via the Hagen-Poiseuille exact solution using Newtonian and three different non-Newtonian models: namely Carreau, power-law and Herschel-Bulkley models. The Weissenberg-Rabinowitsch correction for blood shear-thinning viscosity was applied to the non-Newtonian models. The error percentage between the two sets of models was calculated and discussed. The Newtonian hypothesis was tested statistically and discussed using paired t tests. Significant differences (P < 0.0001) were found between the Newtonian and non-Newtonian WSS in ICA. In MCA and AComA, similar differences were found except in the systole and diastole for the Herschel-Bulkley and power-law models (P = 0.0669, P = 0.7298), respectively. The error between the Newtonian and non-Newtonian models ranged from − 27 to 30% (0.2 to 2.2 Pa). These values could affect the physical interpretation of IA CFD studies. Evidence suggests that the Newtonian assumption may be inappropriate to investigate intracranial hemodynamics. [Figure not available: see fulltext.]. © 2018, International Federation for Medical and Biological Engineering.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2019-evidence-for-non-newtonian-behavior-of-intracrania"
},
{
"id": "scopus-2019-wall-shear-stress-in-the-navier-stokes-equation-a-",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr201982",
"entry_type": "article",
"title": "Wall shear stress in the Navier-Stokes equation: A commentary",
"year": 2019,
"venue": "Computers in Biology and Medicine",
"volume": "106",
"issue": "",
"pages": "82 - 83",
"doi": "10.1016/j.compbiomed.2019.01.012",
"doi_url": "https://doi.org/10.1016/j.compbiomed.2019.01.012",
"scopus_url": "https://www.scopus.com/pages/publications/85060343666?origin=resultslist",
"authors": "Saqr, Khalid M.",
"abstract": null,
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2019-wall-shear-stress-in-the-navier-stokes-equation-a-"
},
{
"id": "scopus-2018-aerodynamics-of-a-trapped-vortex-combustor-a-compa",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Khalil20181",
"entry_type": "article",
"title": "Aerodynamics of a trapped vortex combustor: A comparative assessment of RANS based CFD models",
"year": 2018,
"venue": "Journal of Advanced Research in Fluid Mechanics and Thermal Sciences",
"volume": "43",
"issue": "1",
"pages": "1 - 19",
"doi": "",
"doi_url": "",
"scopus_url": "https://www.scopus.com/pages/publications/85043375294?origin=resultslist",
"authors": "Khalil, Hesham and Saqr, Khalid and Eldrainy, Yehia and Abdelghaffar, Walid",
"abstract": "Trapped vortex combustion, TVC, has shown promising results in terms of wide stability range and low pressure drop. However, previous experimental and numerical studies, which were limited to DNS, have provided only global performance assessments. Also, high computational cost limitations of DNS motivated the need for evaluating other lower cost turbulent models. Consequently, three RANS turbulence models were assessed in the present work; RKE, SST-KW, and RSM, using 2D numerical computations. In addition, the effect of inlet flow Re on cavity flow physics and stability was explored for more detailed physical insight. Ansys Fluent 12 has been used in the computations with the steady state compressible pressure based solver. RSM was found to have the least prediction error percentage against experimental data with maximum value of 12.1% for all cases studied compared with 23.9 % demonstrated by the SST-KW which was the least accurate model. Increasing inlet flow Re by order of magnitude had no apparent effect on the main flow structure for the same cavity size. However, the 300 % Re increase from 9229 to 27687 has led to 10 times increase in turbulence levels and 3 times increase in recirculation zone strength which confirms the high stability range of these combustors. Finally, multiple vortex structures, either behind the forebody for smaller cavity sizes of H/Df < 0.6 or behind the afterbody for larger cavity sizes H/Df > 1, were noticed to be the main reason behind increased pressure drop from 0.8 to 1.1%. This study was conducted as a ground base for future TVC analysis. © 2018 PENERBIT AKADEMIA BARU.",
"publication_stage": "Final",
"public": true,
"evidence_level": "scopus-record-no-doi",
"record_id": "scopus-2018-aerodynamics-of-a-trapped-vortex-combustor-a-compa"
},
{
"id": "scopus-2018-evaluation-criteria-for-a-flameless-combustor-base",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Khalil2018127",
"entry_type": "article",
"title": "Evaluation criteria for a flameless combustor based on recirculation and mixing - A CFD approach",
"year": 2018,
"venue": "Acta Astronautica",
"volume": "152",
"issue": "",
"pages": "127 - 136",
"doi": "10.1016/j.actaastro.2018.07.054",
"doi_url": "https://doi.org/10.1016/j.actaastro.2018.07.054",
"scopus_url": "https://www.scopus.com/pages/publications/85050944141?origin=resultslist",
"authors": "Khalil, Hesham M. and Eldrainy, Yehia A. and Saqr, Khalid M. and Abdelghaffar, Walid A.",
"abstract": "In the present work, the effect of combustor geometry and inlet air velocity on flameless critical parameters such as recirculation ratio and mixing is investigated. The main objective is to develop evaluation criteria for flameless combustors design based on these critical parameters. A simple lab scale combustor with central air jet arrangement is employed for the analysis. Three-dimensional computations were performed under non-reacting conditions using ANSYS Fluent. Reducing the air jet diameter to half its original value leads to a 100% increase in the recirculation ratio, which promotes flameless operation. Moreover, it results in a slightly more than 200% increase in turbulence intensity, which encourages hot products entrainment and accelerates mixing with incoming reactants. From another side, scaling down the combustor to half its original size results in 66% reduction of recirculation ratio, which might suppress flameless operation. Besides, it accelerates incoming reactants mixing in the near burner region due to the increased jet spreading and decay rate. These results show the considerable influence of combustor geometry on recirculation ratio and mixing. Furthermore, the critical role of later parameters in the previously reported transition between conventional and flameless combustion modes for the present combustor is demonstrated. A threshold value of recirculation ratio, Kcritical, is found critical for flameless operation and is noticed to increase with increasing excess air ratio. Therefore, the two parameters are linked together through a developed mathematical correlation. Finally, combustor geometry is represented through the dimensionless parameters; air jet to combustor diameter ratio, and combustor scaling factor. Recirculation ratio is linked to these parameters through additional correlations. Through these developed correlations, geometry aspects for flameless combustors can be preliminary identified and/or evaluated. © 2018 IAA",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2018-evaluation-criteria-for-a-flameless-combustor-base"
},
{
"id": "scopus-2018-improving-indoor-thermal-comfort-by-using-phase-ch",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Abuelnuor20182084",
"entry_type": "article",
"title": "Improving indoor thermal comfort by using phase change materials: A review",
"year": 2018,
"venue": "International Journal of Energy Research",
"volume": "42",
"issue": "6",
"pages": "2084 - 2103",
"doi": "10.1002/er.4000",
"doi_url": "https://doi.org/10.1002/er.4000",
"scopus_url": "https://www.scopus.com/pages/publications/85041135728?origin=resultslist",
"authors": "Abuelnuor, Abuelnuor A. A. and Omara, Adil A. M. and Saqr, Khalid M. and Elhag, Ibrahim H. I.",
"abstract": "Phase change materials (PCMs) have great potentials to be used in modern building materials to stabilize indoor temperature fluctuations for improving thermal comfort. This paper presents a comprehensive review on the use of PCMs in buildings to improve thermal comfort without increasing energy consumption. Concise discussions of the experimental and computational works reported in literature are presented. A special focus of this review is devoted to discussing different analysis methods and models used to test, characterize, and measure the performance of PCMs in modern building applications under different conditions. This detailed review also highlights the special attention given to organic PCMs, such as paraffin, due to their favorable properties, such as low price, chemical stability, non-corrosiveness, and high latent heat of fusion. The review shows the scarcity of literature reporting the use of eutectic PCMs in building applications, despite their high volumetric storage density. Copyright © 2018 John Wiley & Sons, Ltd.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2018-improving-indoor-thermal-comfort-by-using-phase-ch"
},
{
"id": "scopus-2017-computational-fluid-dynamics-study-of-dusty-air-fl",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Zidane20171",
"entry_type": "article",
"title": "Computational fluid dynamics study of dusty air flow over NACA 63415 airfoil for wind turbine applications",
"year": 2017,
"venue": "Jurnal Teknologi",
"volume": "79",
"issue": "7-3",
"pages": "1 - 6",
"doi": "10.11113/jt.v79.11877",
"doi_url": "https://doi.org/10.11113/jt.v79.11877",
"scopus_url": "https://www.scopus.com/pages/publications/85035111796?origin=resultslist",
"authors": "Zidane, Iham F. and Saqr, Khalid M. and Swadener, Greg and Ma, Xianghong and Shehadeh, Mohamed F.",
"abstract": "Gulf and South African countries have enormous potential for wind energy. However, the emergence of sand storms in this region postulates performance and reliability challenges on wind turbines. This study investigates the effects of debris flow on wind turbine blade performance. In this paper, two-dimensional incompressible Navier-Stokes equations and the transition SST turbulence model are used to analyze the aerodynamic performance of NACA 63415 airfoil under clean and sandy conditions. The numerical simulation of the airfoil under clean surface condition is performed at Reynolds number 460×103, and the numerical results have a good consistency with the experimental data. The Discrete Phase Model has been used to investigate the role sand particles play in the aerodynamic performance degradation. The pressure and lift coefficients of the airfoil have been computed under different sand particles flow rates. The performance of the airfoil under different angle of attacks has been studied. Results showed that the blade lift coefficient can deteriorate by 28% in conditions relevant to the Gulf and South African countries sand storms. As a result, the numerical simulation method has been verified to be economically available for accurate estimation of the sand particles effect on the wind turbine blades. © 2017 Penerbit UTM Press. All rights reserved.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2017-computational-fluid-dynamics-study-of-dusty-air-fl"
},
{
"id": "scopus-2017-exergy-analysis-of-garri-2-180-mw-combined-cycle-p",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Abuelnuor2017960",
"entry_type": "article",
"title": "Exergy analysis of Garri “2” 180 MW combined cycle power plant",
"year": 2017,
"venue": "Renewable and Sustainable Energy Reviews",
"volume": "79",
"issue": "",
"pages": "960 - 969",
"doi": "10.1016/j.rser.2017.05.077",
"doi_url": "https://doi.org/10.1016/j.rser.2017.05.077",
"scopus_url": "https://www.scopus.com/pages/publications/85019608741?origin=resultslist",
"authors": "Abuelnuor, A.A.A. and Saqr, Khalid M. and Mohieldein, Siddig Abuelgasim Abbas and Dafallah, Khalid Ahmed and Abdullah, Mohammednour M. and Nogoud, Yasser Abdullah Mahjoub",
"abstract": "Recently, one of the major and serious worldly concerns is the limitation of energy resources. Sudan, in specific, confronts a critical crises relating to fossil fuel resources, and mostly concerning the production of electricity energy from fired thermal power plants. One of these Garri “2” combined cycle power plants produce about 180 MW. In the light of the second law of thermodynamics, exergy analysis is considered a powerful and effective tool to investigate the optimization of engineering devices. In order to evaluate exergetic efficiency and exergy destruction of each part, exergy analysis has been carried out for Garri “2;” while in order to achieve it, exergy balance and entropy generation were analyzed. Conclusively, the results proved that combustion chambers are the main sources of exergy destruction due to their high irreversibility. These results in detail illustrate the following percentages: 63% from the total exergy destruction, followed by 13.6% of gas turbines, 6.4% steam turbines, 6.3% heat recovery steam generators (HRSGs), 4.7% stacks (exhaust gases), 3.8% compressors and 2.3% cooling systems. Moreover, the results affirmed that thermal and exergetic efficiencies for the entire plant are (38%, 49%) respectively. © 2017 Elsevier Ltd",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2017-exergy-analysis-of-garri-2-180-mw-combined-cycle-p"
},
{
"id": "scopus-2017-numerical-investigation-of-turbulent-flow-and-heat",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Abo Elazm20172405",
"entry_type": "article",
"title": "Numerical investigation of turbulent flow and heat transfer over partially open cavities effect of opening ratio",
"year": 2017,
"venue": "Thermal Science",
"volume": "21",
"issue": "6",
"pages": "2405 - 2418",
"doi": "10.2298/tsci150309126a",
"doi_url": "https://doi.org/10.2298/tsci150309126a",
"scopus_url": "https://www.scopus.com/pages/publications/85038637481?origin=resultslist",
"authors": "Abo Elazm, Mohamed M. and Shehata, Ali I. and Saqr, Khalid M.",
"abstract": "Partially open cavities are encountered in various engineering systems such as electronic cooling devices and cooling for gas turbine blades, instead of conventional film cooling slots. Flow is to be imparted over the partially open cavity where it induces a shear layer and a shear driven vortex within the cavity, which is subjected to cooling effect at its wall. Depending on the opening ratio, heat and mass transfer occur between the main flow and the trapped vortex through the shear layer. In the present study, RANS simulations of such flow have been conducted for circular and square cavities to investigate the effect of opening ratio on the heat and mass transfer characteristics. The simulations were established on a rigorous numerical approach and proper validation with laser Doppler velocimetry measurements of turbulent flow in circular cavity. Based on the hydraulic diameter of the cavity, opening ratios ranging from 0.2 to 1.0 were investigated for a Reynolds number of 3·105. Generally, the maximum Nusselt number was achieved at higher opening ratios for both circular and rectangle cavities. On the other hand, the maximum dimensionless temperature gradient, θ, inside the cavity was achieved at L/D = 0.2 for both cavity configurations. © 2017 Society of Thermal Engineers of Serbia.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2017-numerical-investigation-of-turbulent-flow-and-heat"
},
{
"id": "scopus-2017-numerical-simulation-of-the-flow-around-a-subsea-p",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saber2017188",
"entry_type": "article",
"title": "Numerical simulation of the flow around a subsea pipeline with different protection methods",
"year": 2017,
"venue": "Proceedings of the Institution of Mechanical Engineers Part M: Journal of Engineering for the Maritime Environment",
"volume": "231",
"issue": "1",
"pages": "188 - 199",
"doi": "10.1177/1475090216632017",
"doi_url": "https://doi.org/10.1177/1475090216632017",
"scopus_url": "https://www.scopus.com/pages/publications/85017518630?origin=resultslist",
"authors": "Saber, Mohamed and Saqr, Khalid M. and Hassan, Amr A. and Kotb, Mohamed A.",
"abstract": "Hydrodynamic stress induced by marine currents subject subsea pipelines to failure vulnerability. Therefore, several methods have been established to protect such pipelines from hydrodynamic forces. The objective of this work is to investigate the performance of two different protection methods using computational fluid dynamics. A second-order accurate upwind finite volume computational fluid dynamics model was used to simulate isotropic turbulent flow around a subsea pipeline located on flat seabed. A comparison between four turbulence models revealed that both Menter's shear stress transport k-ω and the standard k-ω models yield the best agreement with experimental measurements. Pipeline trenching and double-barrier protection methods were simulated with different geometrical characteristics. A comparison between those two methods was conducted and discussed. It is found that at small aspect ratios, the double-barrier method prevails over trenching in terms of its ability to isolate the pipe from the main current. While at large aspect ratio, trenching provides near-zero pressure coefficient along the pipe wall, which demonstrate its prevalence in protecting the pipeline. © IMechE 2015.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2017-numerical-simulation-of-the-flow-around-a-subsea-p"
},
{
"id": "scopus-2017-numerical-study-for-a-marine-current-turbine-blade",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Dajani2017898",
"entry_type": "conference",
"title": "Numerical Study for a Marine Current Turbine Blade Performance under Varying Angle of Attack",
"year": 2017,
"venue": "Energy Procedia",
"volume": "119",
"issue": "",
"pages": "898 - 909",
"doi": "10.1016/j.egypro.2017.07.143",
"doi_url": "https://doi.org/10.1016/j.egypro.2017.07.143",
"scopus_url": "https://www.scopus.com/pages/publications/85029513880?origin=resultslist",
"authors": "Dajani, S. and Shehadeh, M. and Saqr, K.M. and Elbatran, A.H. and Hart, N. and Soliman, A. and Cheshire, D.",
"abstract": "Energy generation from marine currents is a promising technology for sustainable development. The success of using marine current turbines to tap the ocean hydrodynamic energy depends on predicting the hydrodynamic characteristics and performance of such turbines. This paper presents an analysis of the two dimensional flow using commercial CFD software over a marine current turbine blade. The 2D flow is simulated for HF-SX NACA foil modified from S1210 NACA foil at various angles of attack with Reynolds number of 19×104, which represents the marine current flow. The hydrofoil is designed with considerations for lift and drag coefficients. The flow is simulated by solving the steady-state Navier-Stokes equations coupled with the k-ω shear stress transport (SST) turbulence model. The aim of this work is to study the effect of the angle of attack on the lift and drag coefficients. The computational domain is composed of non-homogenous structured meshing, with sufficient refinement of the domain near the foil blade in order to capture the boundary layer effects. Hence, all calculations are done at constant flow velocity while varying the angle attack for every model tested. The results have shown that the drag and lift coefficient, Cd and Cl coefficient increases with increasing the value of the angle of attack, ratio Cl/Cd curve related on performance at the peak 7°angle of attack. © 2017 The Authors. Published by Elsevier Ltd.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2017-numerical-study-for-a-marine-current-turbine-blade"
},
{
"id": "scopus-2017-passive-flow-control-for-aerodynamic-performance-e",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Shehata201731",
"entry_type": "article",
"title": "Passive flow control for aerodynamic performance enhancement of airfoil with its application in Wells turbine – Under oscillating flow condition",
"year": 2017,
"venue": "Ocean Engineering",
"volume": "136",
"issue": "",
"pages": "31 - 53",
"doi": "10.1016/j.oceaneng.2017.03.010",
"doi_url": "https://doi.org/10.1016/j.oceaneng.2017.03.010",
"scopus_url": "https://www.scopus.com/pages/publications/85015370407?origin=resultslist",
"authors": "Shehata, Ahmed S. and Xiao, Qing and Saqr, Khalid M. and Naguib, Ahmed and Alexander, Day",
"abstract": "In this work, the passive flow control method was applied to improve the performance of symmetrical airfoil section in the stall regime. In addition to the commonly used first law analysis, the present study utilized an entropy generation minimization method to examine the impact of the flow control method on the entropy generation characteristics around the turbine blade. This work is performed using a time-dependent CFD model of isolated NACA airfoil, which refers to the turbine blade, under sinusoidal flow boundary conditions, which emulates the actual operating conditions. Wells turbine is one of the most proper applications that can be applied by passive flow control method because it is subjected to early stall. Additionally, it consists of a number of blades that have a symmetrical airfoil section subject to the wave condition. It is deduced that with the use of passive flow control, torque coefficient of blade increases by more than 40% within stall regime and by more than 17% before the stall happens. A significantly delayed stall is also observed. © 2017 Elsevier Ltd",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2017-passive-flow-control-for-aerodynamic-performance-e"
},
{
"id": "scopus-2017-revisiting-the-lid-driven-cavity-flow-problem-revi",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "AbdelMigid2017123",
"entry_type": "article",
"title": "Revisiting the lid-driven cavity flow problem: Review and new steady state benchmarking results using GPU accelerated code",
"year": 2017,
"venue": "Alexandria Engineering Journal",
"volume": "56",
"issue": "1",
"pages": "123 - 135",
"doi": "10.1016/j.aej.2016.09.013",
"doi_url": "https://doi.org/10.1016/j.aej.2016.09.013",
"scopus_url": "https://www.scopus.com/pages/publications/84991204781?origin=resultslist",
"authors": "AbdelMigid, Tamer A. and Saqr, Khalid M. and Kotb, Mohamed A. and Aboelfarag, Ahmed A.",
"abstract": "This paper presents a broad account of the lid-driven cavity flow problem which is an important benchmark problem for the validation of CFD codes. A comprehensive review of the literature on the problem is presented and discussed, and available benchmarking results are compared in tabulated format to provide a comprehensive source of validation data. In addition, the problem was solved using a Graphical Processing Unit (GPU) accelerated in-house code developed by the authors (https://github.com/TamerAbdelmigid/DrivenCavity_FVM.git), which solves the steady Navier-Stokes equations, using the Finite Volume Method (FVM) in primitive variable formulation. Case studies of steady incompressible flow in a 2D lid-driven square cavity are investigated for 100 < Re < 5000. Detailed second order spatially accurate results are verified and presented in a tabulated form for the sake of serving as benchmark dataset for future works on the same problem. In the present work, collocated grid arrangement along with a uniform structured Cartesian grid up to 1301 × 1301 was used. © 2016 Faculty of Engineering, Alexandria University",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2017-revisiting-the-lid-driven-cavity-flow-problem-revi"
},
{
"id": "scopus-2017-wells-turbine-for-wave-energy-conversion-a-review",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Shehata20176",
"entry_type": "article",
"title": "Wells turbine for wave energy conversion: a review",
"year": 2017,
"venue": "International Journal of Energy Research",
"volume": "41",
"issue": "1",
"pages": "6 - 38",
"doi": "10.1002/er.3583",
"doi_url": "https://doi.org/10.1002/er.3583",
"scopus_url": "https://www.scopus.com/pages/publications/84978901288?origin=resultslist",
"authors": "Shehata, Ahmed S. and Xiao, Qing and Saqr, Khalid M. and Alexander, Day",
"abstract": "In the past 20 years, the use of wave energy systems has significantly increased, generally depending on the oscillating water column concept. Wells turbine is one of the most efficient oscillating water column technologies. This article provides an updated and a comprehensive account of the state-of-the-art research on Wells turbine. Hence, it draws a roadmap for the contemporary challenges, which may hinder future reliance on such systems in the renewable energy sector. In particular, the article is concerned with the research directions and methodologies, which aim at enhancing the performance and efficiency of Wells turbine. The article also provides a thorough discussion of the use of CFD for performance modeling and design optimization of Wells turbine. It is found that a numerical model using the CFD code can be employed successfully to calculate the performance characteristics of W-T as well as other experimental and analytical methods. The increase of research papers about CFD, especially in the last 5 years, indicates that there is a trend that considerably depends on the CFD method. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2017-wells-turbine-for-wave-energy-conversion-a-review"
},
{
"id": "scopus-2016-acceleration-of-computational-fluid-dynamics-simul",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Abdelmigid201615",
"entry_type": "conference",
"title": "Acceleration of Computational Fluid Dynamics Simulations by Parallelization of the Linear Equation Solver Using Wavefront Technique",
"year": 2016,
"venue": "26th International Conference on Computer Theory and Applications, ICCTA 2016 - Proceedings",
"volume": "",
"issue": "",
"pages": "15 - 19",
"doi": "10.1109/iccta40200.2016.9512940",
"doi_url": "https://doi.org/10.1109/iccta40200.2016.9512940",
"scopus_url": "https://www.scopus.com/pages/publications/85114035623?origin=resultslist",
"authors": "Abdelmigid, Tamer A. and Abouelfarag, Ahmed A. and Saqr, Khalid M. and Kotb, Mohamed A.",
"abstract": "Computational fluid dynamics (CFD) uses numerical analysis methods and algorithms to solve and analyze problems that involve fluid flows. These algorithms require very high computational power that does not exist in traditional computers systems. This paper presents code accelerated methodology by parallelizing the linear equation solver and is developed to provide the numerical solution of the steady Navier-Stokes equations, using the Finite Volume Method (FVM) in primitive variables formulation. A case study of incompressible flow in a 2D lid-driven square cavity is investigated for $\\text{Re}=1000$. Detailed second order spatially accurate results, where the tertiary vortices were observed, are presented. Co-located grid arrangements along with a uniform structured Cartesian grid up to ${701}^{\\ast} 701$ were used. Strongly implicit procedure is used to solve the resulted linear algebraic equations. The parallelization of SIP solver is implemented by using wave-front technique and was implemented using OpenMP with multi-core processor. The solution time was reduced by 26%. © 2016 IEEE.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2016-acceleration-of-computational-fluid-dynamics-simul"
},
{
"id": "scopus-2016-cfd-modelling-of-entropy-generation-in-turbulent-p",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr2016999",
"entry_type": "article",
"title": "CFD modelling of entropy generation in turbulent pipe flow: Effects of temperature difference and swirl intensity",
"year": 2016,
"venue": "Applied Thermal Engineering",
"volume": "100",
"issue": "",
"pages": "999 - 1006",
"doi": "10.1016/j.applthermaleng.2016.02.014",
"doi_url": "https://doi.org/10.1016/j.applthermaleng.2016.02.014",
"scopus_url": "https://www.scopus.com/pages/publications/84960921677?origin=resultslist",
"authors": "Saqr, Khalid M. and Shehata, Ali I. and Taha, Ahmed A. and Abo Elazm, Mohamed M.",
"abstract": "This article extends the recent study by Saqr and Wahid (Applied Thermal Engineering 70 (2014) 486-493) on the criteria of heat transfer enhancement in swirl pipe flow based on the entropy generation minimization principle. The effects of wall-fluid temperature difference (ΔT) and swirl intensity (Sn) on entropy generation are considered in the present work. A Computational Fluid Dynamics (CFD) model of non-isothermal swirl pipe flow was developed, validated with established LDA measurements, and then used to study the Nusselt (Nu), entropy augmentation (Ns) and Bejan (Be) numbers in 77 different scenarios related to swirl-enhanced heat exchangers. Critical values of ΔT and Sn that correspond to unity Ns were identified. Then, based on the CFD results, two computer codes were developed in MATLAB software to correlate Ns and Be as functions of ΔT and Sn. These computer codes are openly provided in this article's appendix in order to contribute to the design and optimization tools of swirl-enhanced heat exchangers. © 2016 Elsevier Ltd. All rights reserved.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2016-cfd-modelling-of-entropy-generation-in-turbulent-p"
},
{
"id": "scopus-2016-on-the-role-of-surface-roughness-in-the-aerodynami",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Zidane20162054",
"entry_type": "article",
"title": "On the role of surface roughness in the aerodynamic performance and energy conversion of horizontal wind turbine blades: a review",
"year": 2016,
"venue": "International Journal of Energy Research",
"volume": "40",
"issue": "15",
"pages": "2054 - 2077",
"doi": "10.1002/er.3580",
"doi_url": "https://doi.org/10.1002/er.3580",
"scopus_url": "https://www.scopus.com/pages/publications/84977139296?origin=resultslist",
"authors": "Zidane, Iham F. and Saqr, Khalid M. and Swadener, Greg and Ma, Xianghong and Shehadeh, Mohamed F.",
"abstract": "Renewable energy is one of the main pillars of sustainable development, especially in developing economies. Increasing energy demand and the limitation of fossil fuel reserves make the use of renewable energy essential for sustainable development. Wind energy is considered to be one of the most important resources of renewable energy. In North African countries, such as Egypt, wind energy has an enormous potential; however, it faces quite a number of technical challenges related to the performance of wind turbines in the Saharan environment. Seasonal sand storms affect the performance of wind turbines in many ways, one of which is increasing the wind turbine aerodynamic resistance through the increase of blade surface roughness. The power loss because of blade surface deterioration is significant in wind turbines. The surface roughness of wind turbine blades deteriorates because of several environmental conditions such as ice or sand. This paper is the first review on the topic of surface roughness effects on the performance of horizontal-axis wind turbines. The review covers the numerical simulation and experimental studies as well as discussing the present research trends to develop a roadmap for better understanding and improvement of wind turbine performance in deleterious environments. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2016-on-the-role-of-surface-roughness-in-the-aerodynami"
},
{
"id": "scopus-2016-optimum-operational-performance-of-a-new-stand-alo",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Hassan2016303",
"entry_type": "article",
"title": "Optimum operational performance of a new stand-alone agricultural greenhouse with integrated-TPV solar panels",
"year": 2016,
"venue": "Solar Energy",
"volume": "136",
"issue": "",
"pages": "303 - 316",
"doi": "10.1016/j.solener.2016.07.017",
"doi_url": "https://doi.org/10.1016/j.solener.2016.07.017",
"scopus_url": "https://www.scopus.com/pages/publications/84978264424?origin=resultslist",
"authors": "Hassan, Gasser E. and Salah, Alaa H. and Fath, Hassan and Elhelw, Mohamed and Hassan, Amany and Saqr, Khalid M.",
"abstract": "This study investigates, analytically, the design of a new stand-alone agriculture Green House (GH) designed to be a self-sufficient of energy and irrigation requirements. This design uses Transparent Photo Voltaic (TPV) for electrical power generation and humidification-Dehumidification process for water production. The paper investigates the effect of the location of the condenser(s) for the cooling system, the condenser bypass and fresh air ratios on the internal micro-climatic conditions of the GH. For the hot climatic conditions of Abu Dhabi, UAE, controlling both the condenser bypass and fresh air ratios can be used to satisfy the required micro-climate conditions for plant growth, minimize the power consumption for refrigeration cycle and maximize the water production. According to the operating conditions, water production ranges between 8.3 and 13 L/m2 day which is sufficient for plant needs while the generated electrical power of the TPV is about 10% of the electrical energy requirements which indicates the need for additional PV panels to be installed with the GH system. © 2016 Elsevier Ltd",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2016-optimum-operational-performance-of-a-new-stand-alo"
},
{
"id": "scopus-2016-performance-analysis-of-wells-turbine-blades-using",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Shehata20161123",
"entry_type": "article",
"title": "Performance analysis of wells turbine blades using the entropy generation minimization method",
"year": 2016,
"venue": "Renewable Energy",
"volume": "86",
"issue": "",
"pages": "1123 - 1133",
"doi": "10.1016/j.renene.2015.09.045",
"doi_url": "https://doi.org/10.1016/j.renene.2015.09.045",
"scopus_url": "https://www.scopus.com/pages/publications/84942756725?origin=resultslist",
"authors": "Shehata, Ahmed S. and Saqr, Khalid M. and Xiao, Qing and Shehadeh, Mohamed F. and Day, Alexander",
"abstract": "Wells turbine concept depends on utilizing the oscillating air column generated over marine waves to drive a turbine. As a matter of fact, previous researches on the performance analysis of such turbine were based on the first law of thermodynamics only. Nonetheless, the actual useful energy loss cannot be completely justified by the first law because it does not distinguish between the quantity and the quality of energy. Therefore, the present work investigates the second law efficiency and entropy generation characteristics around different blades that are used in Wells turbine under oscillating flow conditions. The work is performed by using time-dependent CFD models of different NACA airfoils under sinusoidal flow boundary conditions. Numerical investigations are carried out for the incompressible viscous flow around the blades to obtain the entropy generation due to viscous dissipation. It is found that the value of second law efficiency of the NACA0015 airfoil blade is higher by approximately 1.5% than the second law efficiency of the NACA0012, NACA0020 and NACA0021 airfoils. Furthermore, it is found that the angle of attack radically affects the second law efficiency and such effect is quantified for NACA0015 for angle of attack ranging from -15° to 25°. © 2015 Elsevier Ltd.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2016-performance-analysis-of-wells-turbine-blades-using"
},
{
"id": "scopus-2014-a-review-on-the-flow-structure-and-pollutant-dispe",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Yazid2014892",
"entry_type": "article",
"title": "A review on the flow structure and pollutant dispersion in urban street canyons for urban planning strategies",
"year": 2014,
"venue": "SIMULATION",
"volume": "90",
"issue": "8",
"pages": "892 - 916",
"doi": "10.1177/0037549714528046",
"doi_url": "https://doi.org/10.1177/0037549714528046",
"scopus_url": "https://www.scopus.com/pages/publications/84905975862?origin=resultslist",
"authors": "Yazid, Afiq Witri Muhammad and Sidik, nor Azwadi Che and Salim, Salim Mohamed and Saqr, Khalid M",
"abstract": "As a result of rapid urbanization in numerous cities around the world, the demand for transportation has increased rapidly, resulting in emission of high levels of exhaust pollutants into the atmosphere. This is a major cause of deterioration in the local air quality, with consequent escalating risk of adverse health conditions amongst urban inhabitants. Understanding dispersion of pollutants in street canyons, local urban configurations, meteorological processes, and other physical factors are essential for predicting and assessing air quality. This article presents a comprehensive review of the state-of-the-art research works relevant to the investigation of flow structures and pollutant dispersion phenomena in urban street canyons. Various factors, including building geometries, local atmospheric conditions, static and dynamic obstructions, as well as chemical reactions of exhaust pollutants, are critically discussed by taking into account field measurements, wind tunnel experiments, operational modeling techniques, and computational fluid dynamics (CFD). The most critical pollutant levels in street canyons under several physical circumstances are identified. Elements leading to discrepancies and resulting in inconsistencies of different research methods are briefly addressed and suggestions for future research are offered. © 2014, The Society for Modeling and Simulation International. All rights reserved.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2014-a-review-on-the-flow-structure-and-pollutant-dispe"
},
{
"id": "scopus-2014-characteristics-of-biomass-in-flameless-combustion",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Abuelnuor2014363",
"entry_type": "article",
"title": "Characteristics of biomass in flameless combustion: A review",
"year": 2014,
"venue": "Renewable and Sustainable Energy Reviews",
"volume": "33",
"issue": "",
"pages": "363 - 370",
"doi": "10.1016/j.rser.2014.01.079",
"doi_url": "https://doi.org/10.1016/j.rser.2014.01.079",
"scopus_url": "https://www.scopus.com/pages/publications/84897727140?origin=resultslist",
"authors": "Abuelnuor, A.A.A. and Wahid, M.A. and Hosseini, Seyed Ehsan and Saat, A. and Saqr, Khalid M. and Sait, Hani H. and Osman, M.",
"abstract": "The demands of energy and pollutant emissions reduction have motivated the combustion researchers to work on combustion improvement. Flameless combustion or high temperature air combustion has many features such as flame stability, low pollutant emission and uniform profiles of temperature compared to the other modes of combustion. Combustion of solid fuels likes biomass and wastes in flameless combustion conditions has not been investigated as comprehensive as combustion of gaseous fuels. The aim of using biomass in combustion is to reduce the pollutant emissions and to decrease the rate of fossil fuel consumption. In this review, combustion characteristics of biomass in flameless combustion are explained. The paper summarizes the research on the mass loss, ignition time, and NOx emissions during biomass flameless combustion. These summaries show that biomass under flameless combustion gives low pollutant emissions, low mass loss and it decreases the ignition time. © 2014 Elsevier Ltd.",
"publication_stage": "Final",
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"record_id": "scopus-2014-characteristics-of-biomass-in-flameless-combustion"
},
{
"id": "scopus-2014-effects-of-swirl-intensity-on-heat-transfer-and-en",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr2014486",
"entry_type": "article",
"title": "Effects of swirl intensity on heat transfer and entropy generation in turbulent decaying swirl flow",
"year": 2014,
"venue": "Applied Thermal Engineering",
"volume": "70",
"issue": "1",
"pages": "486 - 493",
"doi": "10.1016/j.applthermaleng.2014.05.059",
"doi_url": "https://doi.org/10.1016/j.applthermaleng.2014.05.059",
"scopus_url": "https://www.scopus.com/pages/publications/84902357362?origin=resultslist",
"authors": "Saqr, Khalid M. and Wahid, Mazlan A.",
"abstract": "In the present work, numerical simulations of turbulent incompressible nonisothermal pipe flows were conducted to investigate the effect of inlet swirl intensity and streamwise swirl decay on heat transfer and local entropy generation in the flow. The RANS, energy and entropy equations along with Shih's realizable k-ε turbulence model were numerically solved using second order finite volume upwind discretization scheme. The CFD model results showed very good agreement with established LDV measurements. The streamwise trends of Nusselt and Stanton numbers were studied at different inlet swirl intensities. A new CFD-based empirical correlation for predicting the entropy augmentation number as a function of swirl number was proposed. It is shown that the swirl number radically affects the local entropy generation due to viscous dissipation in the inner core of the Rankine vortex structure. © 2014 Elsevier Ltd. All rights reserved.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2014-effects-of-swirl-intensity-on-heat-transfer-and-en"
},
{
"id": "scopus-2014-entropy-generation-due-to-viscous-dissipation-arou",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Shehata2014808",
"entry_type": "conference",
"title": "Entropy generation due to viscous dissipation around a wells turbine blade: A preliminary numerical study",
"year": 2014,
"venue": "Energy Procedia",
"volume": "50",
"issue": "",
"pages": "808 - 816",
"doi": "10.1016/j.egypro.2014.06.099",
"doi_url": "https://doi.org/10.1016/j.egypro.2014.06.099",
"scopus_url": "https://www.scopus.com/pages/publications/84905693180?origin=resultslist",
"authors": "Shehata, Ahmed S. and Saqr, Khalid M. and Shehadeh, Mohamed and Xiao, Q. and Day, A.H.",
"abstract": "The present work analyzes, through a rigorous numerical investigation, the entropy generation due to viscous dissipation around a Wells turbine blade. Two-dimensional numerical models for four NACA airfoils were built and validated against experimental measurements under steady flow conditions. The models were used to assess the entropy generation for flows achieving 10° angle of attack. It was found that the entropy generation around the NACA0015 airfoil blade is less by approximately 12% than the entropy generation around NACA0012, NACA0020 and NACA0021 airfoils. Then, the NACA0015 and NACA0021 airfoils were simulated under different flow conditions (i.e. Reynolds number and angle of attack). The results were discussed in the light of Wells turbine performance objectives. © 2014 Published by Elsevier Ltd.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2014-entropy-generation-due-to-viscous-dissipation-arou"
},
{
"id": "scopus-2014-experimental-investigation-of-erosion-corrosion-ph",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Shehadeh2014",
"entry_type": "article",
"title": "Experimental investigation of erosion-corrosion phenomena in a steel fitting due to plain and slurry seawater flow",
"year": 2014,
"venue": "International Journal of Mechanical and Materials Engineering",
"volume": "9",
"issue": "1",
"pages": "",
"doi": "10.1186/s40712-014-0022-7",
"doi_url": "https://doi.org/10.1186/s40712-014-0022-7",
"scopus_url": "https://www.scopus.com/pages/publications/84921469929?origin=resultslist",
"authors": "Shehadeh, Mohamed and Anany, Mohammed and Saqr, Khalid M. and Hassan, Ibrahim",
"abstract": "The present work presents an experimental characterization of the erosion-corrosion phenomena caused by confined slurry seawater flow. A set of experiments were conducted under a carefully controlled environment to estimate the erosion-corrosion severity in a 90° pipe bend. Sand particle concentration ranged from 0 to 9 g/l. Accurate spectrometric measurements of eroded iron concentration in the drain flow were carried out in order to characterize the erosion-corrosion severity in the bend. Both the flow Reynolds number and sand particle concentration were directly correlated to the onset of erosion phenomena. Consequently, this study proposes empirical correlations to predict the erosion-corrosion rate as a function of sand concentration and Reynolds number with two sets of coefficients for both laminar and turbulent flow regimes. © 2014 Shehadeh et al.; licensee Springer.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2014-experimental-investigation-of-erosion-corrosion-ph"
},
{
"id": "scopus-2014-numerical-simulations-of-the-effect-of-an-isotropi",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "El-Maghlany2014333",
"entry_type": "article",
"title": "Numerical simulations of the effect of an isotropic heat field on the entropy generation due to natural convection in a square cavity",
"year": 2014,
"venue": "Energy Conversion and Management",
"volume": "85",
"issue": "",
"pages": "333 - 342",
"doi": "10.1016/j.enconman.2014.05.093",
"doi_url": "https://doi.org/10.1016/j.enconman.2014.05.093",
"scopus_url": "https://www.scopus.com/pages/publications/84903123887?origin=resultslist",
"authors": "El-Maghlany, Wael M. and Saqr, Khalid M. and Teamah, Mohamed A.",
"abstract": "Entropy generation associated with laminar natural convection in an infinite square cavity, subjected to an isotropic heat field with different intensities; was numerically investigated for different values of Rayleigh number. The numerical work was carried out using, an in-house CFD code written in FORTRAN, which discretizes non-dimensional forms of the governing equations using the finite volume method and solves the resulting system of equations using Gauss-Seidal method utilizing a TDMA algorithm. Proper code validation was undertaken in order to establish the entropy generation calculations. It was found that the increase in the isotropic heat field intensity resulted in a corresponding exponential increase of the entropy augmentation number, and promoted high values of Bejan number within the flow. The entropy generation due to heat transfer was approximately one order of magnitude higher than the entropy generation due to fluid friction. The spatial uniformity of the Bejan number was more sensitive to the change in Rayleigh number than to the heat field intensity. The thermodynamic penalty of the isotropic heat field is shown by means of global integrals of the entropy source terms over the entire flow domain. © 2014 Elsevier Ltd. All rights reserved.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2014-numerical-simulations-of-the-effect-of-an-isotropi"
},
{
"id": "scopus-2014-on-rans-modeling-of-unconfined-swirl-flow",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Radwan2014159",
"entry_type": "article",
"title": "On rans modeling of unconfined swirl flow",
"year": 2014,
"venue": "CFD Letters",
"volume": "6",
"issue": "4",
"pages": "159 - 174",
"doi": "",
"doi_url": "",
"scopus_url": "https://www.scopus.com/pages/publications/84930750675?origin=resultslist",
"authors": "Radwan, Arabi and Ibrahim, Kamal A. and Hanafy, Ahmed and Saqr, Khalid M.",
"abstract": "This article presents numerical simulations of unconfined swirl flow. The Sydney swirl flow database was used as references for the boundary conditions and experimental validation. A number of RANS turbulence models were investigated in order to explore their potential in predicting axial and swirl velocity profiles of the swirl flow field. The numerical investigations showed that among the tested RANS models, the K−ω showed an acceptable performance in predicting the swirling flow features in both cases (low and high swirl level). The results also demonstrated that the k−ω model was able to provide a reasonably accurate prediction data that is in consistent with experimental measurements at most locations. © 2014 All rights reserved. ISSR Journals",
"publication_stage": "Final",
"public": true,
"evidence_level": "scopus-record-no-doi",
"record_id": "scopus-2014-on-rans-modeling-of-unconfined-swirl-flow"
},
{
"id": "scopus-2013-entropy-generation-in-turbulent-swirl-stabilized-f",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr2013280",
"entry_type": "article",
"title": "Entropy generation in turbulent swirl-stabilized flame: Effect of hydrogen enrichment",
"year": 2013,
"venue": "Applied Mechanics and Materials",
"volume": "388",
"issue": "",
"pages": "280 - 284",
"doi": "10.4028/www.scientific.net/amm.388.280",
"doi_url": "https://doi.org/10.4028/www.scientific.net/amm.388.280",
"scopus_url": "https://www.scopus.com/pages/publications/84884799215?origin=resultslist",
"authors": "Saqr, Khalid M. and Wahid, Mazlan A.",
"abstract": "A set of numerical simulations were conducted to estimate the change in entropy generation in swirl stabilized CH4/air flames due to H2 addition to the fuel. A robust finite volume computational model solving the Reynolds Averaged Navier Stokes with a first order turbulence closure and laminar flamelet combustion model was used to compute the flow and energy fields in the flame. Hydrogen enrichment resulted in an increase in the entropy generation rate of the flame. Such increase was attributed to the increase in heat transfer irreversibilities due to flame temperature rise. © (2013) Trans Tech Publications, Switzerland.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2013-entropy-generation-in-turbulent-swirl-stabilized-f"
},
{
"id": "scopus-2013-numerical-simulation-of-entropy-generation-in-hydr",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr20131",
"entry_type": "article",
"title": "Numerical simulation of entropy generation in hydrogen enriched swirl stabilized combustion",
"year": 2013,
"venue": "CFD Letters",
"volume": "5",
"issue": "1-2",
"pages": "1 - 5",
"doi": "",
"doi_url": "",
"scopus_url": "https://www.scopus.com/pages/publications/84879295444?origin=resultslist",
"authors": "Saqr, Khalid M. and Wahid, Mazlan A.",
"abstract": "Numerical simulations were conducted to estimate the change in entropy generation in swirl stabilized CH4/air flame due to H2 addition to the fuel stream. A finite volume computational model which solves the Reynolds Averaged Navier Stokes with the Rε/k-ε turbulence model and laminar flamelet combustion model was used to compute the flow and energy fields of the flame. The numerical simulation was validated by comparing computed profiles of velocity and mixture fraction with established laser measurements of Sydney swirl burner. It was found that hydrogen enrichment results in an increase in the entropy generation rate of the flame. Such increase was attributed to the increase in heat transfer irreversibilities due to flame temperature rise. © 2013 All rights reserved. ISSR Journals.",
"publication_stage": "Final",
"public": true,
"evidence_level": "scopus-record-no-doi",
"record_id": "scopus-2013-numerical-simulation-of-entropy-generation-in-hydr"
},
{
"id": "scopus-2012-comparison-of-eddy-dissipation-model-and-presumed-",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Rohani2012384",
"entry_type": "conference",
"title": "Comparison of eddy dissipation model and presumed probability density function model for temperature prediction in a non-premixed turbulent methane flame",
"year": 2012,
"venue": "AIP Conference Proceedings",
"volume": "1440",
"issue": "",
"pages": "384 - 391",
"doi": "10.1063/1.4704240",
"doi_url": "https://doi.org/10.1063/1.4704240",
"scopus_url": "https://www.scopus.com/pages/publications/84874399244?origin=resultslist",
"authors": "Rohani, Behzad and Wahid, M.A. and Sies, Mohsin Mohd and Saqr, Khalid M.",
"abstract": "Temperature distribution is predicted through numerical simulation of a turbulent non-premixed methane flame using the standard Eddy Dissipation Model (EDM) and a model based a presumed shape of probability density function (PDF) along with an equilibrium chemistry model. Results are validated against existing experimental data. Two models are compared to each other in terms of accuracy and their advantages and disadvantages are discussed. © 2012 American Institute of Physics.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2012-comparison-of-eddy-dissipation-model-and-presumed-"
},
{
"id": "scopus-2012-computational-study-of-decaying-annular-vortex-flo",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr20124652",
"entry_type": "article",
"title": "Computational study of decaying annular vortex flow using the R ε/k-ε turbulence model",
"year": 2012,
"venue": "Applied Mathematical Modelling",
"volume": "36",
"issue": "10",
"pages": "4652 - 4664",
"doi": "10.1016/j.apm.2011.11.082",
"doi_url": "https://doi.org/10.1016/j.apm.2011.11.082",
"scopus_url": "https://www.scopus.com/pages/publications/84861882061?origin=resultslist",
"authors": "Saqr, Khalid M. and Kassem, Hassan I. and Aly, Hossam S. and Wahid, Mazlan A.",
"abstract": "In this article, we present three dimensional CFD study of turbulent vortex flow in an annular passage using OpenFOAM 1.6. The vortex flow is generated by introducing the flow through a tangential entry to the passage. For the analysis presented in this article, turbulence was modeled using the . R ε/. k-. ε model, in addition, a comparison between such model with the standard . k-. ε model was conducted and discussed. The main characteristics of the flow such as vortex structure and recirculation zone were investigated. It was found that flow is subjected to Rankine vortex structure with three forced vortex regimes and a free vortex region near to the outer wall. The phenomenon of vortex decay was investigated by depicting the swirl number trend along the axial direction of the flow domain. It was found that the vortex decay is subjected to an exponential decay behavior. New coefficients for the exponential decay correlation were derived based on local values of velocity components in different radial planes. © 2011 Elsevier Inc.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2012-computational-study-of-decaying-annular-vortex-flo"
},
{
"id": "scopus-2012-direct-thrust-force-measurement-of-pulse-detonatio",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Wahid20121257",
"entry_type": "conference",
"title": "Direct thrust force measurement of pulse detonation engine",
"year": 2012,
"venue": "AIP Conference Proceedings",
"volume": "1440",
"issue": "",
"pages": "1257 - 1263",
"doi": "10.1063/1.4704344",
"doi_url": "https://doi.org/10.1063/1.4704344",
"scopus_url": "https://www.scopus.com/pages/publications/84874417842?origin=resultslist",
"authors": "Wahid, Mazlan Abdul and Faiz, M. Z. Ahmad and Saqr, Khalid M.",
"abstract": "In this paper we present the result of High-Speed Reacting Flow Laboratory (HiREF) pulse detonation engine (PDE) experimental study on direct thrust measurement. The thrust force generated by the repetitive detonation from a 50 mm inner diameter and 600 mm length tube was directly measured using load cell. Shchelkin spiral was used as an accelerator for the Deflagration to Detonation Transition (DDT) phenomenon. Propane-oxygen at stoichiometric condition was used as the combustible fuel-air mixture for the PDE. The PDE was operated at the operation frequency of 3Hz during the test. The amount of thrust force that was measured during the test reaching up to 70N. These values of thrust force were found to be fluctuating and its combustion phenomenon has been analyzed and discussed. © 2012 American Institute of Physics.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2012-direct-thrust-force-measurement-of-pulse-detonatio"
},
{
"id": "scopus-2012-effects-of-buildings-aspect-ratio-wind-speed-and-w",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Afiq2012158",
"entry_type": "article",
"title": "Effects of buildings aspect ratio, wind speed and wind direction on flow structure and pollutant dispersion in symmetric street canyons: A review",
"year": 2012,
"venue": "International Journal of Mechanical and Materials Engineering",
"volume": "7",
"issue": "2",
"pages": "158 - 165",
"doi": "",
"doi_url": "",
"scopus_url": "https://www.scopus.com/pages/publications/84866646545?origin=resultslist",
"authors": "Afiq, W.M.Y. and Azwadi, C.S.N. and Saqr, K.M.",
"abstract": "The issue of air quality conditions has become a major indicator to the quality of life in many urban areas around the world. It was affected by the air pollution in urban street canyons mainly contributed by the vehicle emitted source. Different street canyon geometry and meteorological conditions may cause pollutant accumulation inside street canyon due to lack of ventilation leading to the air quality deterioration. In the last two decades, numerous researches have been conducted through various research approaches to understand the impact of street canyon configurations and wind flow condition on wind flow structure and pollutant dispersion inside street canyons. This paper intends to review state of the art findings of available research approaches with special intentions been given to the effects of street canyon geometry, wind speed and wind direction on wind flow structure as well as pollutant dispersion in symmetric street canyons.",
"publication_stage": "Final",
"public": true,
"evidence_level": "scopus-record-no-doi",
"record_id": "scopus-2012-effects-of-buildings-aspect-ratio-wind-speed-and-w"
},
{
"id": "scopus-2012-effects-of-hydrogen-addition-on-the-structure-and-",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Rohani2012681",
"entry_type": "article",
"title": "Effects of hydrogen addition on the structure and pollutant emissions of a turbulent unconfined swirling flame",
"year": 2012,
"venue": "International Communications in Heat and Mass Transfer",
"volume": "39",
"issue": "5",
"pages": "681 - 688",
"doi": "10.1016/j.icheatmasstransfer.2012.03.020",
"doi_url": "https://doi.org/10.1016/j.icheatmasstransfer.2012.03.020",
"scopus_url": "https://www.scopus.com/pages/publications/84861578642?origin=resultslist",
"authors": "Rohani, Behzad and Saqr, Khalid M.",
"abstract": "This article aims at investigating the effect of hydrogen addition on the temperature and pollutant emissions of turbulent unconfined swirling methane/air flame. A computational approach utilizing the steady laminar flamelet and the realizable k-ε combustion and turbulence models, respectively, has been used. The turbulence-combustion interaction has been modeled by a β-shaped presumed probability density function. The percentage of hydrogen in the fuel stream is modeled at a wide range from 0% to 50% of the fuel volume flow rate. Results show that with the increase of volumetric hydrogen percentage in the fuel stream the flame structure changes considerably. The size of maximum temperature region decreases significantly to a small region at flame tip and peak temperature rises which leads to increase in NO emission levels. The flame with 10% hydrogen is observed to be slightly of the general trend. This is deemed to be due to the change in flow field as a result of change in fuel density, while the amount of hydrogen is not effective enough to change the combustion characteristics of the flame. © 2012 Elsevier Ltd.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2012-effects-of-hydrogen-addition-on-the-structure-and-"
},
{
"id": "scopus-2012-highly-resolved-large-eddy-simulation-of-the-nonre",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr2012400",
"entry_type": "conference",
"title": "Highly-resolved large eddy simulation of the nonreacting flow in an asymmetric vortex combustor",
"year": 2012,
"venue": "AIP Conference Proceedings",
"volume": "1440",
"issue": "",
"pages": "400 - 408",
"doi": "10.1063/1.4704242",
"doi_url": "https://doi.org/10.1063/1.4704242",
"scopus_url": "https://www.scopus.com/pages/publications/84874423888?origin=resultslist",
"authors": "Saqr, Khalid M. and Wahid, M.A. and Sies, Mohsin M.",
"abstract": "In this paper, we present a computational investigation of the nonreacting flow structure inside a novel asymmetric vortex combustor that was recently proposed by the authors. Large Eddy Simulation using the Smagorinsky-Lilly subgrid turbulence closure has been used to study such flow. A computational grid of 2.22×106 cells was used to ensure that the resolved turbulence kinetic energy is fairly more than 80% of the total turbulence kinetic energy budget. The flow was found to exhibit a central recirculation zone, and two secondary recirculation zones in the asymmetry regions. The vortex structure was found to be a completely forced vortex field. The effect of turbulence on the size and structure of the statistically averaged mean flow phenomena has been analyzed as discussed. © 2012 American Institute of Physics.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2012-highly-resolved-large-eddy-simulation-of-the-nonre"
},
{
"id": "scopus-2012-integrating-a-simplified-p-n-radiation-model-with-",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Kassem2012697",
"entry_type": "article",
"title": "Integrating a simplified P-N radiation model with EdmFoam1.5: Model assessment and validation",
"year": 2012,
"venue": "International Communications in Heat and Mass Transfer",
"volume": "39",
"issue": "5",
"pages": "697 - 704",
"doi": "10.1016/j.icheatmasstransfer.2012.03.009",
"doi_url": "https://doi.org/10.1016/j.icheatmasstransfer.2012.03.009",
"scopus_url": "https://www.scopus.com/pages/publications/84861571295?origin=resultslist",
"authors": "Kassem, Hassan I. and Saqr, Khalid M. and Sies, Mohsin M. and Wahid, Mazlan Abdul",
"abstract": "This work compliments our recently published work of implementing the eddy dissipation turbulent combustion model in OpenFOAM [1]. The major update proposed herein is linking the EdmFoam1.5 solver with radiation modeling libraries in OpenFOAM. The new solver was validated against experimental data for jet and swirling Sydney flame (SM1). Each case was modeled with/without radiation modeling. The results have a fair agreement in general. In jet flame cases, the radiation modeling has a good impact on refining the predicted results. However it has not the same great effect on the swirling flame case. A review of the EDM applications in different reacting flow problems is also presented and discussed. © 2012 Elsevier Ltd.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2012-integrating-a-simplified-p-n-radiation-model-with-"
},
{
"id": "scopus-2011-a-perspective-of-the-malaysian-highway-energy-cons",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr20113873",
"entry_type": "article",
"title": "A perspective of the Malaysian highway energy consumption and future power supply",
"year": 2011,
"venue": "Energy Policy",
"volume": "39",
"issue": "6",
"pages": "3873 - 3877",
"doi": "10.1016/j.enpol.2011.03.034",
"doi_url": "https://doi.org/10.1016/j.enpol.2011.03.034",
"scopus_url": "https://www.scopus.com/pages/publications/79955897168?origin=resultslist",
"authors": "Saqr, Khalid M. and Musa, Md. Nor",
"abstract": "In this short communication, we discuss the energy consumption trends in the Malaysian road transport sector, with a special emphasis on the energy losses due to vehicle aerodynamic drag on highways. The recent trends of energy consumption in the Malaysian road transport sector are reviewed. It is evidently shown that the aerodynamic losses represented exceed 1.2. MTOE annually since 2002. A novel concept of vertical-axis wind turbine (VAWT) farms for harvesting aerodynamic energy losses on Malaysian highways is preliminarily proposed. The novel concept aims at providing a sustainable and green energy source for the lighting of the highway network in the country. © 2011 Elsevier Ltd.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2011-a-perspective-of-the-malaysian-highway-energy-cons"
},
{
"id": "scopus-2011-comments-on-cfd-analysis-on-the-influence-of-helic",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr20112320",
"entry_type": "article",
"title": "Comments on: \"cFD analysis on the influence of helical carving in a vortex flow solar reactor\" by N. Ozalp and D. JayaKrishna (Int. J. Hydrogen Energy 2010: 35, 6248-6260)",
"year": 2011,
"venue": "International Journal of Hydrogen Energy",
"volume": "36",
"issue": "3",
"pages": "2320 - 2322",
"doi": "10.1016/j.ijhydene.2010.11.001",
"doi_url": "https://doi.org/10.1016/j.ijhydene.2010.11.001",
"scopus_url": "https://www.scopus.com/pages/publications/79551650496?origin=resultslist",
"authors": "Saqr, Khalid M.",
"abstract": null,
"publication_stage": "Final",
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},
{
"id": "scopus-2011-comments-on-influence-of-parent-vessel-dominancy-o",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr2011951",
"entry_type": "article",
"title": "Comments on: \"Influence of parent vessel dominancy on fluid dynamics of anterior communicating artery aneurysms\" by T. Hassan, A.A. Hassan, and Y.M. Ahmed (2010) Acta Neurochirurgica, doi: 10.1007/s00701-010-0824-1",
"year": 2011,
"venue": "Acta Neurochirurgica",
"volume": "153",
"issue": "4",
"pages": "951 - 952",
"doi": "10.1007/s00701-010-0886-0",
"doi_url": "https://doi.org/10.1007/s00701-010-0886-0",
"scopus_url": "https://www.scopus.com/pages/publications/79955793055?origin=resultslist",
"authors": "Saqr, Khalid M.",
"abstract": null,
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},
{
"id": "scopus-2011-computational-and-experimental-investigations-of-t",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr2011353",
"entry_type": "article",
"title": "Computational and experimental investigations of turbulent asymmetric vortex flames",
"year": 2011,
"venue": "International Communications in Heat and Mass Transfer",
"volume": "38",
"issue": "3",
"pages": "353 - 362",
"doi": "10.1016/j.icheatmasstransfer.2010.12.001",
"doi_url": "https://doi.org/10.1016/j.icheatmasstransfer.2010.12.001",
"scopus_url": "https://www.scopus.com/pages/publications/79551687597?origin=resultslist",
"authors": "Saqr, Khalid M. and Aly, Hossam S. and Sies, Mohsin M. and Wahid, Mazlan A.",
"abstract": "In the present article we present computational and experimental investigations of a turbulent asymmetric vortex flame. Such flame was created in a novel asymmetric combustor, which is described for the first time in this article. The three dimensional isothermal and reacting flow fields have been described using a computational methodology that impalements the Rε/k-ε and the eddy dissipation turbulence and combustion models, respectively. The computational model is validated for both isothermal and reacting flows. Additionally, the visible flame structure was captured by direct photography at a wide range of equivalence ratios in order to emphasize the exceptional stability of such flame. The mechanism of flame stability and interaction with the forced vortex field is preliminarily discussed. Finally, the basic characteristics of the asymmetric vortex flames are concluded. © 2010 Elsevier Ltd.",
"publication_stage": "Final",
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},
{
"id": "scopus-2011-implementation-of-the-eddy-dissipation-model-of-tu",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Kassem2011363",
"entry_type": "article",
"title": "Implementation of the eddy dissipation model of turbulent non-premixed combustion in OpenFOAM",
"year": 2011,
"venue": "International Communications in Heat and Mass Transfer",
"volume": "38",
"issue": "3",
"pages": "363 - 367",
"doi": "10.1016/j.icheatmasstransfer.2010.12.012",
"doi_url": "https://doi.org/10.1016/j.icheatmasstransfer.2010.12.012",
"scopus_url": "https://www.scopus.com/pages/publications/79551687152?origin=resultslist",
"authors": "Kassem, Hassan I. and Saqr, Khalid M. and Aly, Hossam. S. and Sies, Mohsin M. and Wahid, Mazlan Abdul",
"abstract": "This work discusses the implementation of eddy dissipation model in OpenFOAM CFD toolbox. The code was validated in modeling of confined non-premixed Methane jet flame. The model predictions were extensively compared against published experimental results as well as ANSYS Fluent® predictions. The differences between the implemented model in OpenFOAM and Fluent were demonstrated. © 2010 Elsevier Ltd.",
"publication_stage": "Final",
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},
{
"id": "scopus-2011-large-eddy-simulation-and-preliminary-modeling-of-",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Eldrainy20111104",
"entry_type": "article",
"title": "Large eddy simulation and preliminary modeling of the flow downstream a variable geometry swirler for gas turbine combustors",
"year": 2011,
"venue": "International Communications in Heat and Mass Transfer",
"volume": "38",
"issue": "8",
"pages": "1104 - 1109",
"doi": "10.1016/j.icheatmasstransfer.2011.05.017",
"doi_url": "https://doi.org/10.1016/j.icheatmasstransfer.2011.05.017",
"scopus_url": "https://www.scopus.com/pages/publications/80052161958?origin=resultslist",
"authors": "Eldrainy, Yehia A. and Saqr, Khalid M. and Aly, Hossam S. and Lazim, Tholudin Mat and Jaafar, Mohammad Nazri Mohd",
"abstract": "This work presents a novel swirler with variable blade configuration for gas turbine combustors and industrial burners. The flow dynamics downstream the swirler was explored using Large Eddy Simulation (LES). The resolved turbulence kinetic energy in the region where the flow exhibits the main flow phenomena was well above 80% of the total turbulent kinetic energy of the flow. It was evidently shown that the new swirler produces a central recirculation zone and a Rankine vortex structure which are necessary for swirl flame stabilization. Two Reynolds-averaged NavierStokes (RANS) simulation cases utilizing the standard and realizable k-ε turbulence models were also conducted for two objectives. The first is to demonstrate the validity of RANS/eddy-viscosity models in predicting the main characteristics of swirling flows with comparison to the LES results. The second objective is to comparatively investigate the flow features downstream the new swirler in both co-rotating and counter-rotating blade configurations. The results show that the counter-rotating configuration produces higher turbulence kinetic energy and more compact recirculation zone compared to the co-rotating configuration. © 2011 Elsevier Ltd.",
"publication_stage": "Final",
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},
{
"id": "scopus-2010-a-mathematical-model-for-predicting-spray-atomizat",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Aly2010618",
"entry_type": "article",
"title": "A mathematical model for predicting spray atomization characteristics in an Eulerian-Eulerian framework",
"year": 2010,
"venue": "International Communications in Heat and Mass Transfer",
"volume": "37",
"issue": "6",
"pages": "618 - 623",
"doi": "10.1016/j.icheatmasstransfer.2010.02.003",
"doi_url": "https://doi.org/10.1016/j.icheatmasstransfer.2010.02.003",
"scopus_url": "https://www.scopus.com/pages/publications/77953542089?origin=resultslist",
"authors": "Aly, Hossam S. and Eldrainy, Yehia A. and Saqr, Khalid M. and Lazim, Tholudin M. and Jaafar, Mohammad Nazri Mohd",
"abstract": "A new mathematical model is developed for calculating droplet break-up frequency based on both drag and turbulence induced fragmentation stresses. The droplet break-up model is introduced into a CFD methodology that is based on the Eulerian-Eulerian approach. The CFD solver couples the population balance equation along with the Navier-Stokes equations for predicting the droplets diameter. Finally, preliminary results using this CFD model are presented for the case of a coaxial airblast atomizer and a good agreement with the experimental data is achieved. © 2010 Elsevier Ltd.",
"publication_stage": "Final",
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},
{
"id": "scopus-2010-analyzing-the-effect-of-free-stream-turbulence-on-",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr2010891",
"entry_type": "conference",
"title": "Analyzing the effect of free stream turbulence on gaseous non-premixed flames",
"year": 2010,
"venue": "AIP Conference Proceedings",
"volume": "1225",
"issue": "",
"pages": "891 - 900",
"doi": "10.1063/1.3464941",
"doi_url": "https://doi.org/10.1063/1.3464941",
"scopus_url": "https://www.scopus.com/pages/publications/78549241268?origin=resultslist",
"authors": "Saqr, Khalid M. and Sies, Mohsin M. and Wahid, Mazlan A.",
"abstract": "The effects of free stream turbulence on non-premixed flames are numerically analyzed. The Spalding eddy dissipation mathematical model is used to control the reaction rate by the large-eddy time scale. The turbulence energy production and dissipation rates are simulated by the κ - ε turbulence model in order to investigate the dependence of the combustion properties on free stream turbulence. The reacting NS equations were spatially discretized and solved through a finite volume scheme and a decoupled pressure-velocity approach, respectively. The flame was assumed to be steady-state, two dimensional and axisymmetric. The reported results include the velocity, temperature and turbulent reaction rate along the flame propagation field. It is found that the increase of free stream turbulence intensity reduces the reaction zone significantly, hence, induces the flame extinction process. © 2010 American Institute of Physics.",
"publication_stage": "Final",
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"evidence_level": "doi-and-scopus",
"record_id": "scopus-2010-analyzing-the-effect-of-free-stream-turbulence-on-"
},
{
"id": "scopus-2010-augmentation-of-turbulence-and-mixing-in-gas-turbi",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Eldrainy2010499",
"entry_type": "conference",
"title": "Augmentation of turbulence and mixing in gas turbine combustors by introducing unsteady effects",
"year": 2010,
"venue": "Proceedings of the 2010 International Conference on Mechanical, Industrial, and Manufacturing Technologies, MIMT 2010",
"volume": "",
"issue": "",
"pages": "499 - 504",
"doi": "10.1115/1.859544.paper78",
"doi_url": "https://doi.org/10.1115/1.859544.paper78",
"scopus_url": "https://www.scopus.com/pages/publications/77953442048?origin=resultslist",
"authors": "Eldrainy, Yehia A. and Aly, Hossam S. and Saqr, Khalid M. and Jaafar, Mohammad Nazri Mohd",
"abstract": "Turbulence production and mixing are crucial for flame stability in gas turbine combustors. Designers have relied on fixed geometry swirlers to introduce a tangential component to the inlet air flow in order to sustain a central recirculation zone able to enhance the mixing process and stabilize the flame. In this paper we propose a novel swirler for gas turbine combustors. The new swirler concept is composed of a conventional vane swirler and a rotating element which interrupts the swirling flow. Such unsteady interruption enhances the turbulence and mixing characteristics of the swirling flow. The novel concept is assessed by performing four numerical simulations at four different angular velocities for the rotating element which are 0, 240, 480, and 960 rpm. A trend of increasing turbulence kinetic energy with the rotating element angular velocity was observed.",
"publication_stage": "Final",
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"record_id": "scopus-2010-augmentation-of-turbulence-and-mixing-in-gas-turbi"
},
{
"id": "scopus-2010-computations-of-shear-driven-vortex-flow-in-a-cyli",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr20101072",
"entry_type": "article",
"title": "Computations of shear driven vortex flow in a cylindrical cavity using a modified k-έ turbulence model",
"year": 2010,
"venue": "International Communications in Heat and Mass Transfer",
"volume": "37",
"issue": "8",
"pages": "1072 - 1077",
"doi": "10.1016/j.icheatmasstransfer.2010.06.021",
"doi_url": "https://doi.org/10.1016/j.icheatmasstransfer.2010.06.021",
"scopus_url": "https://www.scopus.com/pages/publications/77956055710?origin=resultslist",
"authors": "Saqr, Khalid M. and Aly, Hossam S. and Kassem, Hassan I. and Sies, Mohsin M. and Wahid, Mazlan A.",
"abstract": "In this paper, a new variant of the k-έ turbulence model (Saqr et al., CFD Letters, 1(2) pp. 87-94) is used to compute the shear driven vortex flow in an open cylindrical cavity. The results are compared with published LDA measurements for such flow configuration. The modified turbulence model demonstrated good agreement with experimental results, which further supports its validity in computing vortex dominated flows. © 2010 Elsevier Ltd.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2010-computations-of-shear-driven-vortex-flow-in-a-cyli"
},
{
"id": "scopus-2010-effect-of-free-stream-turbulence-on-nox-and-soot-f",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr2010611",
"entry_type": "article",
"title": "Effect of free stream turbulence on NOx and soot formation in turbulent diffusion CH4-air flames",
"year": 2010,
"venue": "International Communications in Heat and Mass Transfer",
"volume": "37",
"issue": "6",
"pages": "611 - 617",
"doi": "10.1016/j.icheatmasstransfer.2010.02.008",
"doi_url": "https://doi.org/10.1016/j.icheatmasstransfer.2010.02.008",
"scopus_url": "https://www.scopus.com/pages/publications/77953543707?origin=resultslist",
"authors": "Saqr, Khalid M. and Aly, Hossam S. and Sies, Mohsin M. and Wahid, Mazlan A.",
"abstract": "A two-dimensional axisymmetric RANS numerical model was solved to investigate the effect of increasing the turbulence intensity of the air stream on the NOx and soot formation in turbulent methane diffusion flames. The turbulence-combustion interaction in the flame field was modelled in a kε ε/EDM framework, while the NO and soot concentrations were predicted through implementing the extended Zildovich mechanism and two transport equations model, respectively. The predicted spatial temperature gradients showed acceptable agreement with published experimental measurements. It was found that the increase of free stream turbulence intensity of the air supply results in a significant reduction in the NO formation of the flame. Such phenomenon is discussed by depicting the spatial distribution of the NO concentration in the flame. An observable reduction of the soot formation was also found to be associated with the increase of inlet turbulence intensity of air stream. © 2010 Elsevier Ltd.",
"publication_stage": "Final",
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"record_id": "scopus-2010-effect-of-free-stream-turbulence-on-nox-and-soot-f"
},
{
"id": "scopus-2010-experiments-on-combustion-kernel-growth-in-gaseous",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr2010225",
"entry_type": "conference",
"title": "Experiments on combustion kernel growth in gaseous explosions",
"year": 2010,
"venue": "AIP Conference Proceedings",
"volume": "1225",
"issue": "",
"pages": "225 - 235",
"doi": "10.1063/1.3464861",
"doi_url": "https://doi.org/10.1063/1.3464861",
"scopus_url": "https://www.scopus.com/pages/publications/78549254896?origin=resultslist",
"authors": "Saqr, Khalid M. and Wahid, Mazlan Abdul and Ujir, Haffis and Sies, Mohsin M.",
"abstract": "The tempo-spatial evolution of the combustion kernel in gas phase explosions was experimentally investigated using Schlieren photography. Methane and propane -air explosions were initiated in a cylindrical explosion vessel at a range of equivalence ratios ranging from 0.6 to 1.4. All explosions were initiated using 25 mj ignition energy at ambient conditions. The kernel growth rate, and cellular flame structure are observed and analyzed. © 2010 American Institute of Physics.",
"publication_stage": "Final",
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"record_id": "scopus-2010-experiments-on-combustion-kernel-growth-in-gaseous"
},
{
"id": "scopus-2010-high-speed-schlieren-photography-of-confined-gaseo",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr2010152",
"entry_type": "article",
"title": "High-speed schlieren photography of confined gaseous explosions",
"year": 2010,
"venue": "International Journal of Mechanical and Materials Engineering",
"volume": "5",
"issue": "2",
"pages": "152 - 162",
"doi": "",
"doi_url": "",
"scopus_url": "https://www.scopus.com/pages/publications/78651456577?origin=resultslist",
"authors": "Saqr, K.M. and Wahid, M.A. and Sies, M.M. and Ujir, M.H.",
"abstract": "The tempo-spatial evolution of the combustion kernel in gas phase explosions was experimentally investigated using millisecond-resolution Schlieren photography. Methane and propane -air explosions were initiated in a cylindrical explosion vessel at a range of equivalence ratios ranging from 0.6 to 1.4. All explosions were initiated using a 25 mJ ignition energy source at ambient conditions. The explosion kernel growth rate and cellular flame structure are observed and analyzed. The growth of the primary flame kernel in propane-air explosions was found to be slower than that of the methane-air explosions, for lean mixtures. The opposite was found for stoichiometric and rich mixtures. The establishment of the cellular structure was found to occur after a certain period of time, which varies according to the fuel type and equivalence ratio.",
"publication_stage": "Final",
"public": true,
"evidence_level": "scopus-record-no-doi",
"record_id": "scopus-2010-high-speed-schlieren-photography-of-confined-gaseo"
},
{
"id": "scopus-2010-ideal-detonation-characteristics-of-biogashydrogen",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr201069",
"entry_type": "conference",
"title": "Ideal detonation characteristics of biogashydrogen and -hydrogen peroxide mixtures",
"year": 2010,
"venue": "International Conference on Theoretical and Applied Mechanics, International Conference on Fluid Mechanics and Heat and Mass Transfer - Proceedings",
"volume": "",
"issue": "",
"pages": "69 - 72",
"doi": "",
"doi_url": "",
"scopus_url": "https://www.scopus.com/pages/publications/79958750544?origin=resultslist",
"authors": "Saqr, Khalid M. and Kassem, Hassan I. and Sies, Mohsin M. and Wahid, Mazlan A.",
"abstract": "This article reports the ideal detonation characteristics of various mixtures of biogas-hydrogen and biogas-hydrogen peroxide with air. The results obtained by the chemical equilibrium calculations reveal the fundamental improvement of the biogas detonation characteristics when it is mixed with either H2 or H2O2. However, a discussion is conducted to compare between the effects of each of those two secondary fuels on the detonation CJ velocity, pressure rise, and temperature of biogas detonation. It was found that in lean mixtures, H2 provides higher detonation speed than H2O2 at the same equivalence ratio.",
"publication_stage": "Final",
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"evidence_level": "scopus-record-no-doi",
"record_id": "scopus-2010-ideal-detonation-characteristics-of-biogashydrogen"
},
{
"id": "scopus-2010-large-eddy-simulation-of-shear-driven-vortex-flow-",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr201084",
"entry_type": "conference",
"title": "Large Eddy Simulation of shear-driven vortex flow in a cylindrical cavity",
"year": 2010,
"venue": "International Conference on Theoretical and Applied Mechanics, International Conference on Fluid Mechanics and Heat and Mass Transfer - Proceedings",
"volume": "",
"issue": "",
"pages": "84 - 87",
"doi": "",
"doi_url": "",
"scopus_url": "https://www.scopus.com/pages/publications/79958737074?origin=resultslist",
"authors": "Saqr, Khalid M. and Aly, Hossam S. and Kassem, Hassan I. and Sies, Mohsin M. and Wahid, Mazlan A.",
"abstract": "Large Eddy Simulation (LES) of the two dimensional shear-driven flow in a cylindrical cavity has been performed to shed the light on the dynamics of the vortex core. Four different Reynolds numbers were considered in the present analysis. The time averaged velocity profiles inside the cavity showed excellent agreement with published LDA measurements. A recent LES methodology proposed by authors was used to demonstrate the essentially weak turbulent characteristics of the vortex core.",
"publication_stage": "Final",
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"evidence_level": "scopus-record-no-doi",
"record_id": "scopus-2010-large-eddy-simulation-of-shear-driven-vortex-flow-"
},
{
"id": "scopus-2010-large-eddy-simulation-the-demand-for-a-universal-m",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr2010ii",
"entry_type": "article",
"title": "Large Eddy Simulation: The demand for a universal measure of resolution",
"year": 2010,
"venue": "CFD Letters",
"volume": "2",
"issue": "1",
"pages": "ii - iii",
"doi": "",
"doi_url": "",
"scopus_url": "https://www.scopus.com/pages/publications/80052182008?origin=resultslist",
"authors": "Saqr, Khalid M.",
"abstract": null,
"publication_stage": "Final",
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"record_id": "scopus-2010-large-eddy-simulation-the-demand-for-a-universal-m"
},
{
"id": "scopus-2010-numerical-simulation-of-turbulent-dispersion-and-a",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Aly2010505",
"entry_type": "conference",
"title": "Numerical simulation of turbulent dispersion and atomization within sprays",
"year": 2010,
"venue": "Proceedings of the 2010 International Conference on Mechanical, Industrial, and Manufacturing Technologies, MIMT 2010",
"volume": "",
"issue": "",
"pages": "505 - 510",
"doi": "10.1115/1.859544.paper79",
"doi_url": "https://doi.org/10.1115/1.859544.paper79",
"scopus_url": "https://www.scopus.com/pages/publications/77953456318?origin=resultslist",
"authors": "Aly, Hossam S. and Eldrainy, Yehia A. and Saqr, Khalid M. and Jaafar, Mohammad Nazri Mohd",
"abstract": "We present a finite volume CFD methodology for modeling liquid dispersion and atomization within sprays. The proposed CFD model is based on the Eulerian multi-fluid approach, i.e., the mass and momentum conservation equations are solved for both phases. The population balance equation is solved along with the Navier-Stokes equations for tracking droplet diameters. To introduce the physics of spray atomization processes into the population balance equation, a new mathematical model is developed for calculating droplet break up frequency and included in the population balance equation as a source term. This new model calculates the droplet break up frequency based on both drag and turbulence induced fragmentation stresses. Finally, preliminary results using this CFD model are presented for the case of a coaxial airblast atomizer and a good agreement with the experimental data is achieved.",
"publication_stage": "Final",
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"evidence_level": "doi-and-scopus",
"record_id": "scopus-2010-numerical-simulation-of-turbulent-dispersion-and-a"
},
{
"id": "scopus-2010-performance-of-rans-turbulence-models-in-predictin",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Kassem201073",
"entry_type": "conference",
"title": "Performance of RANS turbulence models in predicting strained flows in a curved duct",
"year": 2010,
"venue": "International Conference on Theoretical and Applied Mechanics, International Conference on Fluid Mechanics and Heat and Mass Transfer - Proceedings",
"volume": "",
"issue": "",
"pages": "73 - 77",
"doi": "",
"doi_url": "",
"scopus_url": "https://www.scopus.com/pages/publications/79958759506?origin=resultslist",
"authors": "Kassem, Hassan I. and Aly, Hossam S. and Saqr, Khalid M. and Sies, Mohsin M. and Wahid, Mazlan A.",
"abstract": "In this paper, we assess the performance of four RANS turbulence models in computing the averaged flow field through a curved duct. The Models studied are the standard k-ω, the standard k-ω, The Reynolds Stress Model, and the v2 f model. Although the four models showed similar quantitative agreement for the tangential velocity profile with experimental measurements, it was only the v2 f model that correctly predicted the expected secondary flow pattern. Moreover, the V2f model was the only model to capture the zero turbulence kinetic energy areas in which laminarization of the flow occur.",
"publication_stage": "Final",
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"evidence_level": "scopus-record-no-doi",
"record_id": "scopus-2010-performance-of-rans-turbulence-models-in-predictin"
},
{
"id": "scopus-2010-single-pulse-detonation-study-of-natural-gas",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Mat Zin201078",
"entry_type": "conference",
"title": "Single pulse detonation study of natural gas",
"year": 2010,
"venue": "International Conference on Theoretical and Applied Mechanics, International Conference on Fluid Mechanics and Heat and Mass Transfer - Proceedings",
"volume": "",
"issue": "",
"pages": "78 - 83",
"doi": "",
"doi_url": "",
"scopus_url": "https://www.scopus.com/pages/publications/79958710577?origin=resultslist",
"authors": "Mat Zin, Ahmad Faiz and Wahid, Mazlan A. and Saqr, Khalid M. and Ujir, Haffis",
"abstract": "In the present paper, we report the single pulse detonation study using natural gas as the fuel. The detonation tube used was measured to be 1500 mm in length with 100 mm of internal diameter. The target of this research is to study the effect variable percentage of oxygen used as oxidizer and nitrogen as the diluents gas to the pulse detonation combustion of natural gas. The effects of different level of ignition energy used to initiate the pulse combustion and variable length of obstacle arrangement also being reported. The result shows that, from the experimental investigations natural gas is less sensitive to form detonation combustion for any percentage of nitrogen dilution. It is observed that the flame is propagating at high speed turbulent flame combustion except for longer length of obstacle it shows detonation propagations.",
"publication_stage": "Final",
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},
{
"id": "scopus-2010-theoretical-notes-on-the-mathematical-modelling-of",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr20101476",
"entry_type": "article",
"title": "Theoretical notes on the mathematical modelling of gaseous detonations using boltzmann equation",
"year": 2010,
"venue": "Journal of Applied Sciences",
"volume": "10",
"issue": "14",
"pages": "1476 - 1480",
"doi": "10.3923/jas.2010.1476.1480",
"doi_url": "https://doi.org/10.3923/jas.2010.1476.1480",
"scopus_url": "https://www.scopus.com/pages/publications/77953782048?origin=resultslist",
"authors": "Saqr, K.M. and Sidik, N.A.C. and Wahid, M.A.",
"abstract": "In this study, we present some theoretical notes on the use of the Boltzmann equation in computing detonation of combustible gases. The scarceness of relevant study, as well as the sensitivity of the topic, were the major motivations behind the intention to present these notes for publication. A timeline of the detonation phenomenon and its physical comprehension was drawn to justify the unsuitability of the continuum hypothesis of describing gaseous detonations. Then, the theory behind the Boltzmann equation and DSMC is elaborated. Finally, a discussion of the available study on the topic is introduced and concluded. © 2010 Asian Network for Scientific Information.",
"publication_stage": "Final",
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"record_id": "scopus-2010-theoretical-notes-on-the-mathematical-modelling-of"
},
{
"id": "scopus-2010-transient-characteristics-of-c3h8-o2-turbulent-mix",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr2010325",
"entry_type": "conference",
"title": "Transient characteristics of C3H8/O2 turbulent mixing in a hypersonic pulse detonation engine",
"year": 2010,
"venue": "Proceedings of the 9th WSEAS International Conference on Applications of Computer Engineering, ACE '10",
"volume": "",
"issue": "",
"pages": "325 - 330",
"doi": "",
"doi_url": "",
"scopus_url": "https://www.scopus.com/pages/publications/79952602810?origin=resultslist",
"authors": "Saqr, Khalid M. and Faiz, Ahmed and Kassem, Hassan and Sies, Mohsin and Wahid, Mazlan A.",
"abstract": "We present the results of a time-dependent three-dimensional numerical simulation of the turbulent mixing characteristics in the mixing chamber of a hypersonic pulse detonation engine (PDE). Fuel (C3H8) was injected through one supersonic injector, while the oxidizer (O2) were injected through four supersonic injectors. The spatial distributions of air to fuel to ratios were traced during 240 millisecond in the mixing chamber of the PDE. The 3D velocity variations was observed as well.",
"publication_stage": "Final",
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"evidence_level": "scopus-record-no-doi",
"record_id": "scopus-2010-transient-characteristics-of-c3h8-o2-turbulent-mix"
},
{
"id": "scopus-2010-whirling-flames-for-fuel-economy-and-low-nox-combu",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr20101057",
"entry_type": "conference",
"title": "Whirling flames for fuel economy and low NOx combustion",
"year": 2010,
"venue": "AIP Conference Proceedings",
"volume": "1225",
"issue": "",
"pages": "1057 - 1059",
"doi": "10.1063/1.3464845",
"doi_url": "https://doi.org/10.1063/1.3464845",
"scopus_url": "https://www.scopus.com/pages/publications/78549258493?origin=resultslist",
"authors": "Saqr, Khalid M. and Sies, Mohsin M. and Ujir, Haffis and Wahid, Mazlan A.",
"abstract": "We present the results of a numerical and experimental investigations of turbulent whirling (i.e. vortex) gaseous flames in an asymmetric cylinder. The flame was found to be stable near the lean flammability limit of methane, which suggests enhanced fuel economy. The flame was also found to have lower rates of NOx compared to other flame configurations at similar equivalence ratio. © 2010 American Institute of Physics.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2010-whirling-flames-for-fuel-economy-and-low-nox-combu"
},
{
"id": "scopus-2009-can-large-eddy-simulation-les-predict-laminar-to-t",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Aly200942",
"entry_type": "article",
"title": "Can large eddy simulation (LES) predict laminar to turbulent flow transition?",
"year": 2009,
"venue": "International Journal of Mechanical and Materials Engineering",
"volume": "4",
"issue": "1",
"pages": "42 - 48",
"doi": "",
"doi_url": "",
"scopus_url": "https://www.scopus.com/pages/publications/70349868321?origin=resultslist",
"authors": "Aly, Hossam S. and Saqr, Khalid M. and Eldrainy, Yehia A. and Jaafar, Mohammad Nazri",
"abstract": "Four numerical experiments have been conducted using Large Eddy Simulation (LES) to visualize laminar and turbulent incompressible flows over a horizontal finite cylinder. The unsteady velocity fluctuations were studied at a point on the near wake downstream the cylinder. These fluctuations were used, through the fundamental understanding of LES mechanism, as indications of the LES sensitivity in capturing the occurrence of transitional flow. Such proved sensitivity is deemed to depend on the Reynolds number and problem physics. The purpose of this study is to investigate the capability of LES in capturing laminar-to-turbulent transitional flow dynamics. Moreover, the present article describes a generalized methodology to use LES in predicting the spatial and temporal onsets of transitional flow. The significance of this study is pointed out from the fundamental dilemma of predicting transitional flow, and the wide application domain of such phenomena.",
"publication_stage": "Final",
"public": true,
"evidence_level": "scopus-record-no-doi",
"record_id": "scopus-2009-can-large-eddy-simulation-les-predict-laminar-to-t"
},
{
"id": "scopus-2009-cfd-analysis-of-incompressible-turbulent-swirling-",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "El Drainy2009562",
"entry_type": "article",
"title": "CFD analysis of incompressible turbulent swirling flow through Zanker plate",
"year": 2009,
"venue": "Engineering Applications of Computational Fluid Mechanics",
"volume": "3",
"issue": "4",
"pages": "562 - 572",
"doi": "10.1080/19942060.2009.11015291",
"doi_url": "https://doi.org/10.1080/19942060.2009.11015291",
"scopus_url": "https://www.scopus.com/pages/publications/85059959692?origin=resultslist",
"authors": "El Drainy, Yehia A. and Saqr, Khalid M. and Aly, Hossam S. and Jaafar, Mohammad Nazri Mohd",
"abstract": "Zanker plate is a widely used flow straightener to eliminate turbulence originating from pipe fittings in experimental fluid flow applications. In this paper, steady state, incompressible, swirling turbulent flow through Zanker plate has been studied. The solution and the analysis were carried out using finite volume CFD solver FLUENT 6.2. Five turbulence models were used in the numerical investigation and their results were compared with the pressure drop correlation of BS EN ISO 5167-2:2003. The turbulence models investigated here are the standard k-ε, realizable k-ε, the Reynolds Stress Model (RSM), the large Eddy Simulation (LES), and the Detached Eddy Simulation (DES). The results showed that the DES model gave the best agreement with the ISO pressure drop correlation, therefore, the model was used further to predict streamline patterns, vortex formations and separated flow regions. The effects of Zanker plate thickness and Reynolds number on the flow characteristics have been investigated as well. © 2019, Taylor and Francis Ltd. All rights reserved.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2009-cfd-analysis-of-incompressible-turbulent-swirling-"
},
{
"id": "scopus-2009-cfd-insight-of-the-flow-dynamics-in-a-novel-swirle",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Eldrainy2009936",
"entry_type": "article",
"title": "CFD insight of the flow dynamics in a novel swirler for gas turbine combustors",
"year": 2009,
"venue": "International Communications in Heat and Mass Transfer",
"volume": "36",
"issue": "9",
"pages": "936 - 941",
"doi": "10.1016/j.icheatmasstransfer.2009.06.013",
"doi_url": "https://doi.org/10.1016/j.icheatmasstransfer.2009.06.013",
"scopus_url": "https://www.scopus.com/pages/publications/70249131753?origin=resultslist",
"authors": "Eldrainy, Yehia A. and Saqr, Khalid M. and Aly, Hossam S. and Jaafar, Mohammad Nazri Mohd",
"abstract": "We describe the flow dynamics inside a novel swirler conceptualized for gas turbine combustors. The supreme advantage in this swirler is the ability to vary the swirl number for the same value of Reynolds number. The significance of such advantage against contemporary configurations, which have constant swirl number, is quite evident at low turbine operating loads. The novel geometry and flow pattern are described in details in the present work. The results of four numerical simulations are presented and discussed to study the central recirculation zone, turbulence intensity, and pressure drop at different swirl numbers. The new concept is deemed to enhance the combustion efficiency because of its ability to adjust the swirl number according to the turbine operating load. The current study reports preliminary results which verify the concept behind the proposed swirler. However, intensive numerical and experimental studies are necessary to be carried out in order to characterize the flow dynamics produced by the novel swirler and its impact on the combustion process. © 2009 Elsevier Ltd. All rights reserved.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2009-cfd-insight-of-the-flow-dynamics-in-a-novel-swirle"
},
{
"id": "scopus-2009-critical-review-of-thermoelectrics-in-modern-power",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr2009165",
"entry_type": "article",
"title": "Critical review of thermoelectrics in modern power generation applications",
"year": 2009,
"venue": "Thermal Science",
"volume": "13",
"issue": "3",
"pages": "165 - 174",
"doi": "10.2298/tsci0903165s",
"doi_url": "https://doi.org/10.2298/tsci0903165s",
"scopus_url": "https://www.scopus.com/pages/publications/77649285874?origin=resultslist",
"authors": "Saqr, Khalid M. and Musa, Mohd N.",
"abstract": "The thermoelectric complementary effects have been discovered in the nineteenth century. However, their role in engineering applications has been very limited until the first half of the twentieth century, the beginning of space exploration era. Radioisotope thermoelectric generators have been the actual motive for the research community to develop efficient, reliable and advanced thermoelectrics. The efficiency of thermoelectric materials has been doubled several times during the past three decades. Nevertheless, there are numerous challenges to be resolved in order to develop thermoelectric systems for our modern applications. This paper discusses the recent advances in thermoelectric power systems and sheds the light on the main problematic concerns which confront contemporary research efforts in that field.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2009-critical-review-of-thermoelectrics-in-modern-power"
},
{
"id": "scopus-2009-numerical-simulation-of-confined-vortex-flow-using",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr200987",
"entry_type": "article",
"title": "Numerical simulation of confined vortex flow using a modified k-ε turbulence model",
"year": 2009,
"venue": "CFD Letters",
"volume": "1",
"issue": "2",
"pages": "87 - 94",
"doi": "",
"doi_url": "",
"scopus_url": "https://www.scopus.com/pages/publications/77956062230?origin=resultslist",
"authors": "Saqr, Khalid M. and Aly, Hossam S. and Wahid, Mazlan A. and Sies, Mohsin M.",
"abstract": "The turbulent flow in a tangential inlet / tangential outlet vortex tube is numerically simulated using a modified K-ε turbulence model. The results are compared to experimental measurements from literature. The modified model shows better agreement with the local tangential velocity measurements compared to the standard and RNGk K-ε turbulence models. The flow structure is also demonstrated using the modified turbulence model. © 2009-2012 All rights reserved. ISSR Journals.",
"publication_stage": "Final",
"public": true,
"evidence_level": "scopus-record-no-doi",
"record_id": "scopus-2009-numerical-simulation-of-confined-vortex-flow-using"
},
{
"id": "scopus-2009-numerical-study-of-the-heat-transfer-augmentation-",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr200962",
"entry_type": "article",
"title": "Numerical study of the heat transfer augmentation in pipes with internal discontinous longetudinal fins",
"year": 2009,
"venue": "International Journal of Mechanical and Materials Engineering",
"volume": "4",
"issue": "1",
"pages": "62 - 69",
"doi": "",
"doi_url": "",
"scopus_url": "https://www.scopus.com/pages/publications/70349876403?origin=resultslist",
"authors": "Saqr, Khalid M. and Musa, Md.N.",
"abstract": "Internally finned (i.e. ribbed) pipes are ideal to be used in flow-based waste heat recovery applications, where the internal heat transfer coefficient has a radical effect on the overall application efficiency. Such pipes provide significantly higher heat transfer coefficient than plain pipes. Compared to helically finned pipes, pipes with internal longitudinal fins have lower pressure drop. The principal objective of this paper is to investigate the effect of repetitive fin discontinuity on the convective heat transfer coefficient for pipes with internal longitudinal fins. A CFD model was used to study the heat transfer augmentation resulting from disturbing the thermal boundary layer by repetitive discontinuities in the fin lateral profile. The CFD model was validated against published empirical correlations for internally finned pipes with compressible viscous flow. Stanton number, Nusselt number and the convective heat transfer coefficient are computed for three different geometries at constant heat transfer coefficient on the outer wall. The effects of both continuous and discontinuous fins on heat transfer are elucidated. A new correlation to predict the temperature drop per unit length as a function of discontinuity offset distance is presented.",
"publication_stage": "Final",
"public": true,
"evidence_level": "scopus-record-no-doi",
"record_id": "scopus-2009-numerical-study-of-the-heat-transfer-augmentation-"
},
{
"id": "scopus-2009-uncharacteristic-phenomenon-in-the-nonisothermal-t",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr2009879",
"entry_type": "conference",
"title": "Uncharacteristic phenomenon in the nonisothermal taylor-couette flow",
"year": 2009,
"venue": "2009 International Conference on Signal Processing Systems, ICSPS 2009",
"volume": "",
"issue": "",
"pages": "879 - 883",
"doi": "10.1109/icsps.2009.191",
"doi_url": "https://doi.org/10.1109/icsps.2009.191",
"scopus_url": "https://www.scopus.com/pages/publications/70449641178?origin=resultslist",
"authors": "Saqr, Khalid M. and Sidik, Nor Azwadi C. and Aly, Hossam S. and ElDrainy, Yehia A.",
"abstract": "We report an uncharacteristic discontinuity locus numerically observed in the 2D nonisothermal Taylor-Couette flow at Re=85 to 622. Five numerical experiments were performed in order to study this phenomenon at different angular velocities. The Navier-Stokes equations were solved in the discretised X-Y space using a finite volume, pressure based approach for the unsteady flow between two concentric cylinders. The inner cylinder was subjected to constant heat flux and constant angular velocity, while the outer cylinder was fixed and maintained at constant temperature. The ratio between the outer and inner cylinder diameters was restricted to the Golden Ratio. © 2009 IEEE.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2009-uncharacteristic-phenomenon-in-the-nonisothermal-t"
},
{
"id": "scopus-2008-development-of-novel-control-strategy-for-multiple",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Khamis Mansour20081455",
"entry_type": "article",
"title": "Development of novel control strategy for multiple circuit, roof top bus air conditioning system in hot humid countries",
"year": 2008,
"venue": "Energy Conversion and Management",
"volume": "49",
"issue": "6",
"pages": "1455 - 1468",
"doi": "10.1016/j.enconman.2007.12.032",
"doi_url": "https://doi.org/10.1016/j.enconman.2007.12.032",
"scopus_url": "https://www.scopus.com/pages/publications/42749083798?origin=resultslist",
"authors": "Khamis Mansour, M. and Musa, Md Nor and Wan Hassan, Mat Nawi and Saqr, Khalid M.",
"abstract": "A novel control strategy to improve energy efficiency and to enhance passengers' thermal comfort of a new roof top bus multiple circuit air conditioning (AC) system operating on partial load conditions is presented. A novel strategy for automatic control of the AC system was developed based on numerous experimental test runs at various operating conditions, taking into account energy saving and thermal comfort without sacrificing the proper cycling rate of the system compressor. For this task, more than 50 test runs were conducted at different set point temperatures of 21, 22 and 23 °C. Fanger's method was used to evaluate passenger thermal comfort, and the system energy consumption was also calculated. A performance comparison between that of the conventional AC system and that of the newly developed one has been conducted. The comparison revealed that the adopted control strategy introduces significant improvements in terms of thermal comfort and energy saving on various partial load conditions. Potential energy saving of up to 31.6% could be achieved. This results in a short payback period of 17 months. It was found from the economic analysis that the new system is able to save approximately 20.0% of the life cycle cost. © 2008 Elsevier Ltd. All rights reserved.",
"publication_stage": "Final",
"public": true,
"evidence_level": "doi-and-scopus",
"record_id": "scopus-2008-development-of-novel-control-strategy-for-multiple"
},
{
"id": "scopus-2008-thermal-design-of-automobile-exhaust-based-thermoe",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Saqr2008155",
"entry_type": "article",
"title": "Thermal design of automobile exhaust based thermoelectric generators: Objectives and challenges",
"year": 2008,
"venue": "International Journal of Automotive Technology",
"volume": "9",
"issue": "2",
"pages": "155 - 160",
"doi": "10.1007/s12239-008-0020-y",
"doi_url": "https://doi.org/10.1007/s12239-008-0020-y",
"scopus_url": "https://www.scopus.com/pages/publications/41749105498?origin=resultslist",
"authors": "Saqr, K.M. and Mansour, M.K. and Musa, M.N.",
"abstract": "The potential for thermoelectric power generation (via waste heat recovery onboard automobiles) to displace alternators and/or provide additional charging to a vehicle battery pack has increased with recent advances in thermoelectric material processing. In gasoline fueled vehicles (GFVs), about 40% of fuel energy is wasted in exhaust heat, while a smaller amount of energy (30%) is ejected through the engine coolant. Therefore, exhaust-based thermoelectric generators (ETEG) have been a focus for GFV applications since the late 1980s. The conversion efficiency of modern thermoelectric materials has increased more than three-fold in the last two decades; however, disputes as to the thermal design of ETEG systems has kept their overall efficiency at limited and insufficient values. There are many challenges in the thermal design of ETEG systems, such as increasing the efficiency of the heat exchangers (hot box and cold plate), maintaining a sufficient temperature difference across the thermoelectric modules during different operating conditions, and reducing thermal losses through the system as a whole. This paper focuses on a review of the main aspects of thermal design of ETEG systems through various investigations performed over the past twenty years. This paper is organized as follows: first, the construction of a typical ETEG is described. The heat balance and efficiency of ETEG are then discussed. Then, the third section of this paper emphasizes the main objectives and challenges for designing efficient ETEG systems. Finally, a review of ETEG research activities over the last twenty years is presented to focus on methods used by the research community to address such challenges. © 2008 Springer.",
"publication_stage": "Final",
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"evidence_level": "doi-and-scopus",
"record_id": "scopus-2008-thermal-design-of-automobile-exhaust-based-thermoe"
},
{
"id": "scopus-2007-development-of-a-novel-control-strategy-for-a-mult",
"source": "Scopus BibTeX export",
"source_export_date": "2026-06-25",
"bibtex_key": "Khamis Mansour2007200",
"entry_type": "article",
"title": "Development of a novel control strategy for a multiple-circuit roof-top bus air-conditioning system in hot humid countries",
"year": 2007,
"venue": "International Journal of Mechanical and Materials Engineering",
"volume": "2",
"issue": "2",
"pages": "200 - 211",
"doi": "",
"doi_url": "",
"scopus_url": "https://www.scopus.com/pages/publications/39549096471?origin=resultslist",
"authors": "Khamis Mansour, M. and Musa, Md. Nor and Hassan, Mat Nawi Wan and Abdullah, Hayati and Saqr, Khalid M.",
"abstract": "A novel control strategy to improve energy efficiency and to enhance passengers' thermal comfort of a new roof-top bus multiple-circuit air-conditioning (AC) system operating on partial load conditions is presented. The new multiple-circuit AC system consists of two evaporators, two condensers, two expansion valves, and two equal capacity compressors. Each one of the evaporators is split up into two halves, one-half of the evaporator coil of one circuit pairing with one-half of the other circuit. A novel strategy for an automatic control of the AC system was developed based on numerous experimental test runs at various operating conditions, taking into account energy saving and thermal comfort without sacrificing the proper cycling rate of the system compressor. For this task, more than 50 test runs were conducted at different set-point temperatures of 21, 22, and 23°C. Fanger's method was used to evaluate the passenger thermal comfort and the system energy consumption was also calculated. A performance comparison between that of the conventional AC system and the newly developed one has been conducted. The comparison revealed that the adopted control strategy introduces significant improvements in terms of thermal comfort and energy saving on various partial load conditions, with potential energy saving of up to 30.8% could be achieved. This results in a short payback period of 19 months. It was found from the economic analysis that the new system is able to save approximately 19.7% of the life cycle cost.",
"publication_stage": "Final",
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"evidence_level": "scopus-record-no-doi",
"record_id": "scopus-2007-development-of-a-novel-control-strategy-for-a-mult"
}
]