A5053292740- Advanced Thermodynamic Systems and Engines
- Refrigeration and Air Conditioning Technologies
- Combustion and flame dynamics
- Spacecraft and Cryogenic Technologies
- Fluid Dynamics and Vibration Analysis
- Advanced Thermodynamics and Statistical Mechanics
- Advanced Combustion Engine Technologies
- Composite Material Mechanics
- Fluid Dynamics and Turbulent Flows
- Heat Transfer and Boiling Studies
- Vibration and Dynamic Analysis
- Combustion and Detonation Processes
- Textile materials and evaluations
- Thermal Radiation and Cooling Technologies
- Optical Network Technologies
- Radiative Heat Transfer Studies
- Phytochemicals and Antioxidant Activities
- Plant biochemistry and biosynthesis
- Fatigue and fracture mechanics
- Acoustic Wave Phenomena Research
- Enhanced Recovery After Surgery
- Material Properties and Processing
- Epoxy Resin Curing Processes
- Cavitation Phenomena in Pumps
- Model Reduction and Neural Networks
Cairo University
2004-2024
Massachusetts Institute of Technology
2022-2023
Mansoura University
1993-2021
Mansoura University Hospital
2021
Benha University
2020
Zagazig University
2019
American University in Cairo
2012-2016
University of Illinois Urbana-Champaign
2006-2013
Alexandria University
2012
Abstract Background Anastomotic leaks (AL) are among the most serious complications due to substantial impact on quality of life and mortality. Inspite advance in diagnostic tools such as laboratory tests radiological adjuncts, only moderate improvement has been recorded rate detected leaks. The purpose research was assess perioperative risk factors for AL. Methods This study achieved at MUH MIH/Egypt within period between January 2016 2019 candidates who underwent bowel anastomosis small...
Views Icon Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Twitter Facebook Reddit LinkedIn Tools Reprints and Permissions Cite Search Site Citation A. I. Abd El-Rahman, C. L. Tucker; Mechanics of random discontinuous long-fiber thermoplastics. Part II: Direct simulation uniaxial compression. J. Rheol. 1 September 2013; 57 (5): 1463–1489. https://doi.org/10.1122/1.4818804 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley...
The design, the manufacture and testing of a novel refrigeration system that is based on thermoacoustic energy-conversion technology reported. A 1-D linear acoustic model specifically developed carefully implemented in present device. consists two similar harmonically-oscillating pistons driven by commercial 1-HP rotary drive mechanism operating at frequency 42 Hz -hereby, replacing typical expensive drivers-, stack within which energy conversion sound into heat taken place. Air ambient...
Partially polymerized membranes display a striking mechanical transition at low temperature known as the wrinkling transition. Fluorescence and scanning electron microscopy well profile measurements using an atomic force microscope revealed existence of three degrees depending on degree membrane polymerization. At polymerization undergoes cascade to form folded phase with characteristic exponent $\ensuremath{\eta}$ equal 3, intermediate polymerization, is in intermediate-wrinkled (similar...
The thermal interactions between the stack plates and their neighboring gas particles within penetration depth in a thermoacoustic resonator convert acoustic energy into heat process of standing refrigeration systems. Few numerical approximations describe flow behavior flux density devices, but almost no simulation results are available for fully coupled continuity Navier–Stokes equations. Here, we report two-dimensional computational fluid dynamics nonlinear oscillating helium-filled...
Transition modeling represents one of the key challenges in computational fluid dynamics. While numerical efforts were traditionally devoted to either improving Reynolds-averaged Navier–Stokes-based turbulence or developing scale-resolving simulations, cautious attention has been recently given field inversion and machine learning techniques. This paper discusses an updated development model for transitional flows based on k–ω shear stress transport using continuous adjoint approach, instead...
The deformation mechanics of dry networks large-aspect-ratio fibers with random orientation controls the processing long-fiber thermoplastics (LFTs) and greatly affects mechanical properties final composites. Here, we generate initial geometries fiber in a cubic unit cell aspect ratio l/d = 100 fully periodic boundary conditions for later numerical simulation. irreversible sequential adsorption (RSA) process is first used to quasi-random structure due excluded-volume requirements. In order...
This study investigates the protective effect of Egyptian acacia pod extracts against overdose paracetamol-induced liver damage. green and brown pods were extracted by mixture ethanol 80%: HCl (6 M) (99:1 v/v). In pods, total phenolic content in hydrolyzed ethyl acetate fraction (HEF) at pH 4, was 649.89 712.14 mg GAE/g while antioxidant activity 95.55% 97.35%, both being highest than any fraction. HEF (pH 4) analyzed HPLC, there 22 compounds rich vanillin about 227 mg/g 11 flavonoids...
A few linear theories [Swift, J. Acoust. Soc. Am. 84(4), 1145–1180 (1988); Swift, 92(3), 1551–1563 (1992); Olson and 95(3), 1405–1412 (1994)] numerical models, based on low-Mach number analysis [Worlikar Knio, Comput. Phys. 127(2), 424–451 (1996); Worlikar et al., 144(2), 199–324 Hireche Canadian 36(3), 164–165 (2008)], describe the flow dynamics of standing-wave thermoacoustic engines, but almost no simulation results are available that enable prediction behavior practical engines...
This work is concerned with the study of slip phenomenon in centrifugal pumps and evaluation its dependence on flow rate for a four-bladed pump. The finite volume method used, impeller domain represented by structured grid topology. calculations assume rotationally periodic boundary condition, while frozen rotor technique used to model interaction between pump surrounding volute casing. simulation uses an implicit time integration dynamic equations carried out using commercial ANSYS...
The flow transition from laminar to turbulent inside of typical thermoacoustic devices influences the heat-exchange capacities these and dramatically impacts overall performances as well. A few measurements [Eckmann Grotberg (1991), J. Fluid Mech. 222, 329–350; Hino, Sawamoto, Takasu (1976). 75, 193–207] direct simulations [Feldmann Wagner (2012). Turbul. 13(32), 1–28; Feldmann (2016a). New Results in Numerical Experimental Mechanics X, pp. 113–122] were reported that describe transitional...
The geometry of airfoil sections in small wind turbine blades affect the boundary layer separation, promote flow transition to turbulence and consequently influence performance many types turbines. However, few optimization results are available for typical blades. Here, we report a particular shape study standard SG6043 that applies genetic algorithm along with low-Re XFOIL solver. numerical model is first validated against experimental values at Reynolds number 100, 000. predicted lift...
Flue gas analyzers, such as those based on electrochemical cells and infrared sensors, are commonly used to determine the molar concentrations of different species flue-gas mixtures provide information about associated air-fuel ratio resulting combustion efficiency. Here, a new methodology for quaternary-gas analysis that relies thermoacoustic technology is described determination composition typical flue gases [A. I. Abd El-Rahman et al., “Thermoacoustic analyzer,” EG Patent: International...
Reliable monitoring of industrial flue gases is essential for maintaining optimal combustion efficiencies, and thus lesser environmental impacts, in the processing typical systems. Typical modern-day sensors rely their operations on either electrochemical or nondispersive infrared technologies. Although such technologies are well established, they also have drawbacks, which include relatively high cost, drift effects, need frequent calibration, limited lifetime. This study investigates...
Abstract Transition modeling in complex flow situations including adverse pressure gradient, streamline curvature, and massive separation represents one of the key challenges computational fluid dynamics that greatly affects characteristics many thermal sciences applications. Here, we report a comparative study helps investigate capability curvature-sensitive kT−kL−ω−v2 transition model against original kT−kL−ω algorithm predicting behavior surrounding smooth circular cylinder subjected to...