Mohamed Gad-el-Hak, Ph.D.

Professor Emeritus | Mechanical & Nuclear Engineering

Fluid mechanics expert, with a penchant for nanotechnology and microelectromechanical systems.

Email: gadelhak@vcu.edu

Areas of Expertise

Fluids in motion, Turbulence and flow control, Viscous pumps and microturbines, Micro- and nanotechnology, Large-scale disasters, Microelectromechanical Systems

Biography

Mohamed Gad-el-Hak was born in Tanta, Egypt, but grew up in Cairo. He received his B.Sc. (summa cum laude) in mechanical engineering from Ain Shams University in 1966 and his Ph.D. in fluid mechanics from the Johns Hopkins University in 1973, under Stanley Corrsin. Gad-el-Hak lived in the United States of America since 1968, and became a U.S. citizen in 1981.

Gad-el-Hak was senior research scientist and program manager at Flow Research Company in Seattle, Washington, and then professor of aerospace and mechanical Engineering at the University of Notre Dame, finally coming to Virginia Commonwealth University in 2002 as chair of mechanical engineering, later mechanical and nuclear engineering. He has also worked at the University of Southern California, University of Virginia, Institut National Polytechnique de Grenoble, Université de Poitiers, Friedrich-Alexander-Universität Erlangen-Nürnberg, Technische Universität München, and Technische Universität Berlin.

Education

Ain Shams University, Cairo, Egypt

B.Sc.
Mechanical Engineering
1966

The Johns Hopkins University

Ph.D.
Fluid Mechanics
1973

Selected Articles

Suppressing Taylor vortices in a Taylor--Couette flow system with free surface
69th Annual Meeting of the APS Division of Fluid Dynamics
2016

Taylor--Couette flows have been extensively investigated due to their many industrial applications, such as catalytic reactors, electrochemistry, photochemistry, biochemistry, and polymerization. Mass transfer applications include extraction, tangential filtration, crystallization, and dialysis. A 3D study is carried out to simulate a Taylor--Couette flow with a rotating and pulsating inner cylinder. We utilize FLUENT to simulate the incompressible flow with a free surface. The study reveals that flow structuring is initiated with the development of an Ekman vortex at low Taylor number, Ta =0.01. For all encountered flow regimes, the Taylor vortices are systematically inhibited by the pulsatile motion of the inner cylinder. A spectral analysis shows that this pulsatile motion causes a rapid decay of the free surface oscillations, from a periodic wavy movement to a chaotic one, then to a fully turbulent motion. This degenerative free surface behavior is interpreted as the underlying mechanism responsible for the inhibition of the Taylor vortices.

Enhanced Turbulence in the Taylor-Couette Flow System
Procedia Engineering
2016

The Taylor-Couette system keeps making subject to countless studies. It is used in catalytic reactors, electrochemistry, photochemistry, biochemistry and polymerization, as well as in mass transfer operations (extraction, tangential filtration, crystallization and dialysis). This work deals with a numerical study dedicated to a Taylor-Couette flow considering the influence of a pulsatile dynamic superimposed to the rotative inner cylinder. Simulations are implemented on the FLUENT commercial package where a three-dimensional and incompressible flow is considered. It is shown that the suggested controlling technique fundamentally alters the physical flow behavior resulting in substantial turbulence enhancement to which transition is instilled at a Taylor number of Ta = 17 instead of Ta = 41.33 corresponding to the non-controlled case.

Nine Decades of Fluid Mechanics
Journal of Fluids Engineering
2016

As the ASME Division of Fluids Engineering celebrates its 90th Anniversary, I make a broad-brush sweep of progress in the field of fluid mechanics during this period. Selected theoretical, numerical, and experimental advances are described. The inventions of laser and computer have profound effects on humanity, but their influence on fluid mechanics is particularly elucidated in this review.