Mohamed Gad-el-Hak

Mohamed Gad-el-Hak is an engineering scientist, currently the Inez Caudill Eminent Professor of biomedical engineering and professor of mechanical & nuclear engineering at Virginia Commonwealth University in Richmond, VA.

Professor Mohamed Gad-el-Hak is an engineering scientist, globally well-known in the field of classical physics and the subfields of mechanics, biomechanics, fluid mechanics, turbulence, flow control, microelectromechanical systems (MEMS), microfluidics, and nanotechnology.He is a prolific writer of technical as well as non-technical books, articles, and essays.

Gad-el-Hak was born on 11 February 1945 in Tanta, Egypt, a city in the heart of the Nile Delta, 94 km north of Cairo.Gad-el-Hak’s elementary, secondary, and tertiary public education took place in Cairo.He received a B.Sc. in mechanical engineering from Ain Shams University in 1966, where he graduated summa cum laude and ranked first in his class.Gad-el-Hak moved to USA in 1968 to start his graduate studies.He received a Ph.D. degree in fluid mechanics in 1973 from the Johns Hopkins University under the tutelage of Professor Stanley Corrsin.(Corrsin’s graduate advisors at Caltech were Hans W. Liepmann and Theodore von Kármán.The latter’s doctoral advisor at Göttingen was Ludwig Prandtl.)Gad-el-Hak’s doctoral thesis is entitled “Experiments on the Nearly Isotropic Turbulence Behind a Jet-Grid”.

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, subsequently expanded to 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.

Gad-el-Hak has been described as original, pioneering, visionary, creative, indefatigable, non-conformist, having breadth and depth, and ahead of the curve.His teaching is innovative, rigorous, and does not appeal to the lowest common denominator, and his research is always leading edge.One of Professor Gad-el-Hak unique accomplishments is his ability to invent a novel measuring technique when none existed.He has done that with laser-induced fluorescence, compliant coating deformation, wind-waves characterizations, viscous micropumping, superhydrophobic surface longevity, amount of entrapped air, and microscale thickness, among others.

Gad-el-Hak is known for developing novel diagnostic tools for turbulent flows, including the laser-induced fluorescence (LIF) technique for flow visualization; and for discovering the efficient mechanism via which a turbulent region rapidly grows by destabilizing a surrounding laminar flow.He has conducted the seminal experiments that detailed the fluid–compliant surface interactions in turbulent boundary layers; introduced the concept of targeted control to achieve drag reduction, lift enhancement, and mixing augmentation in wall-bounded flows; and developed a novel viscous pump suited for microelectromechanical systems (MEMS) applications.His work on Reynolds number effects in turbulent boundary layers, published in 1994, marked a paradigm shift in the subject.His 1999 paper on the fluid mechanics of microdevices established the fledgling field on firm physical grounds and is one of the most cited articles of the 1990s.

Gad-el-Hak is the author of the book Flow Control: Passive, Active, and Reactive Flow Management, and editor of the books Frontiers in Experimental Fluid Mechanics, Advances in Fluid Mechanics Measurements, Flow Control: Fundamentals and Practices, The MEMS Handbook (three volumes), and Large-Scale Disasters: Prediction, Control, and Mitigation.

Below are more details of Gad-el-Hak’s scholarly accomplishments:

1. Authored the first archival paper to describe the laser-induced fluorescence (LIF) flow visualization technique (“On the Growth of Turbulent Regions in Laminar Boundary Layers,” Journal of Fluid Mechanics, vol. 110, pp. 73–95, 1981).The novelty lies in the ability to generate a very thin sheet of laser light as to be able to see one plane at a time, and the use of minuscule amounts of fluorescent dye as not to make the fluid’s interior opaque.Among the technique's advantages are its high signal-to-noise ratio and its ability to dissect the flow field, as a CAT scan would to solid objects.LIF is now routinely used in numerous laboratories around the world, for both gas and liquid flows.

2. First to place the fledgling field of microfluidics on firm physical ground.His 1999 paper comprehensively accomplishing that feat has been cited 1,570 times.Whole books, graduate-level courses, and funding programs sprang worldwide as a result of this paper.

3. His work on Reynolds number effects in turbulent boundary layers, first published in 1994 and continuing throughout the 2000s, marked a significant paradigm shift in the subject.Funding programs in DARPA, ONR, and AFOSR were inspired by Gad-el-Hak's groundbreaking paper.

4. Conducted the seminal experiments that detailed the fluid–compliant surface interactions in turbulent boundary layers.He also introduced a non-invasive technique to probe the coating’s instability waves.The laser-based probe has a spatial resolution of 1 micron and temporal resolution of several kHz.

5. Introduced the concept of selective/targeted/opposition/reactive control to achieve drag reduction, lift enhancement, and mixing augmentation in wall-bounded flows.This patented closed-loop control is now researched intensively around the world. Entire scientific conferences and funding programs are dedicated to reactive (in contrast to active) control.

6. Identified the mechanism by which a turbulent region grows into a laminar, vortical flow.The efficient growth by destabilization mechanism is an order of magnitude more effective than the traditional entrainment process in which a turbulent region incorporates/engulfs the surrounding irrotational flow.

7. Developed a novel viscous pump suited for microelectromechanical systems (MEMS) applications.Inertial pumps, such as axial and centrifugal pumps, do not work at low Reynolds numbers.The only type that worked for MEMS, prior to introducing Gad-el-Hak’s rotary pump, was of the reciprocating variety.

8. Gad-el-Hak’s recent work on large-scale disasters resulted in the establishment of a universal metric by which the severity of all natural and manmade disasters is measured.His book on the subject was the first in the U.S. and second in the world to view large-scale disasters from the physical point of view, in contrast to the social, psychological, logistical, or medical viewpoints.

9. He was among the first group of aerodynamicists in the United States to work on the Supermaneuverability research program, a word coined by the German aerodynamicist Wolfgang Herbst. The DARPA/AFOSR unsteady aerodynamics program formed the foundation for the million plus Unmanned Aerial Vehicles (UAV) flying today.

10. Gad-el-Hak’s recent analytical, numerical, and experimental research on superhydrophobic coatings resulted in better understanding of the fledgling field.Twenty journal publications, including two invited review articles, resulted from our three-year effort.Two measurement techniques were introduced for the first time: (i) an in situ, noninvasive probe to assess the longevity of such coatings; and (ii) a method to measure the coating’s thickness down to the microscale as well as the amount of entrapped air in the coating’s micropockets.

11. Gad-el-Hak’s research covers an extraordinary range of Reynolds, Mach, and Knudsen numbers.His recent work on hypersonic flows identified a new principle for aerodynamic heating.The resulting journal papers were independently highlighted in 2018 by two prestigious publications: American Institute of Physics’ SciLight, and Oxford’s National Science Review.

12. He initiated a nuclear engineering program within the VCU department of mechanical engineering, which he chaired from 2002 to 2009.The unit is now known as the department of mechanical & nuclear engineering, and is the only one in the state of Virginia that offers bachelor’s, master’s, and doctoral degrees in both disciplines.

13. Gad-el-Hak is the first engineering professor to develop and teach a writing course for advanced undergraduate and beginning graduate students in science and engineering.The class is writing intensive and, through assessments, has proven to be more effective than similar classes taught by English and communications faculty.The VCU semester-long course has also been offered by Gad-el-Hak as a short course in other universities.

14. An essay Gad-el-Hak penned for The Chronicle of Higher Education, “We Must Stop the Avalanche of Low-Quality Research”, was chosen in 2011 by the British Science Council to be part of a standardized English examination.

Gad-el-Hak authored 140 journal papers and 52 essays in magazines and newspapers.He has been featured in NPR, PBS, Nature (journal), and The New York Times.Additional to working in the broad field of mechanics, he penned essays and op/ed’s on global warming, energy crisis, proliferation of scholarly publications, massive open online courses (MOOC), university governance, [[Science, technology, engineering, and mathematics STEM and the humanities, engineering education, and societal values of basic research.

Gad-el-Hak’s papers have been cited (as of August 2020) 15,100 times in the technical literature, and his h-index is 54, i100-index is 28, and i10-index is 145. Two of Gad-el-Hak’s books have been translated into Chinese, and several of his articles/essays have been translated into Arabic, Chinese, the Czech language, French, German, Japanese, Russian, Spanish, and Turkish.

Gad-el-Hak delivered over 313 invited lectures in 24 countries.He is a consultant to the United Nations, the governments of twelve countries, and numerous academic and industrial concerns.

Gad-el-Hak has been a member of several advisory panels for DOD, DOE, NASA, and NSF. During the 1991/1992 academic year, he was a visiting professor at Institut de Mécanique de Grenoble, France.During the summers of 1993, 1994, and 1997, he was, respectively, a distinguished faculty fellow at Naval Undersea Warfare Center, Newport, Rhode Island, a visiting exceptional professor at Université de Poitiers, France, and a Gastwissenschaftler (guest scientist) at Forschungszentrum Rossendorf, Dresden, Germany.

Gad-el-Hak is a fellow of the American Academy of Mechanics, a fellow and life member of the American Physical Society, a fellow of the American Institute of Physics, a fellow of the American Society of Mechanical Engineers, a fellow of the American Association for the Advancement of Science, an associate fellow of the American Institute of Aeronautics and Astronautics, and a member of the European Mechanics Society.Gad-el-Hak served as editor of eight international journals, including AIAA Journal, Applied Mechanics Reviews, and Bulletin of the Polish Academy of Sciences.He is additionally a contributing editor for Springer-Verlag’s Lecture Notes in Engineering and Lecture Notes in Physics, for McGraw-Hill’s Year Book of Science and Technology, and for CRC Press’s Mechanical Engineering Series.

To honor Professor Gad-el-Hak, six academicians from three countries penned the editorial “Homage to a Legendary Dynamicist on His Seventy-Fifth Birthday”.The article appeared in the July 2020 issue of the Journal of Fluids Engineering.

In 1998, Gad-el-Hak was named the Fourteenth ASME Freeman Scholar.In 1999, he was awarded the prestigious Alexander von Humboldt Prize as well as the Japanese Government Research Award for Foreign Scholars.In 2002, he was named ASME Distinguished Lecturer.Gad-el-Hak has also been awarded the ASME Medal for seminal contributions to the discipline of fluids engineering, as well as a Certificate of Appreciation in testimony of the high regard of his associates and the deep appreciation of the society for his valued services in advancing the engineering profession.

Gad-el-Hak, M. (2019) “Academic Malaise: Bring Back the Groves of Academe,” Academic Questions, vol. 32, pp. 384–391.

Gad-el-Hak, M. (2019) “Coherent Structures and Flow Control: Genesis and Prospect,” Bulletin of the Polish Academy of Sciences, vol. 67, pp. 411–444.

Zhu, Y., Lee, C., Chen, X., Wu, J., Chen, S., and Gad-el-Hak, M. (2018) “Newly Identified Principle for Aerodynamic Heating in Hypersonic Flows,” Journal of Fluid Mechanics, vol. 855, pp. 152–180.

Ullah, R., Khraisheh, M., Esteves, R.J., McLeskey, J.T., AlGhouti, M., Gad-el-Hak, M., and Vahedi, Tafreshi, H. (2018) “Energy Efficiency of Direct Contact Membrane Distillation,” Desalination, vol. 433, pp. 56–67.

Hemeda, A.A., Esteves, R.J.A., McLeskey, J.T., Gad-el-Hak, M., Khraisheh, M., and Vahedi Tafreshi, H. (2018) “Molecular Dynamic Simulations of Fibrous Distillation Membranes,” International Communications in Heat and Mass Transfer, vol. 98, pp. 304–309.

Gad-el-Hak, M. (2017) “In Defense of Science: What Would John Do?” Physics of Fluids, vol. 29, pp. 020602.1–020602.10.

Gad-el-Hak, M. (2016) “Nine Decades of Fluid Mechanics,” Journal of Fluids Engineering, vol. 138, pp. 100803.1–100803.10.

Gad-el-Hak, M. (2013) “STEM: Salmon Fishing in the US,” The Free Lance-Star, 30 June 2013, pp. D1–D3.

Gad-el-Hak, M. (2010) “Where Is Global Warming When We Need It?” The Free Lance-Star, 21 March, pp. D1–D3.

Gad-el-Hak, M. (2008) Large-Scale Disasters: Prediction, Control, and Mitigation, 600 pages, Cambridge University Press, London.

Gad-el-Hak, M. (2006) Flow Control: Passive, Active, and Reactive Flow Management, 448 pages, Cambridge University Press, London.

Gad-el-Hak, M. (2006) The MEMS Handbook, in three volumes, 1680 pages, CRC Taylor & Francis, Boca Raton, Florida.

Gad-el-Hak, M. (2004) “Publish or Perish—An Ailing Enterprise?,” Physics Today, vol. 57, March, pp. 61–62.

Gad-el-Hak, M. (1999) “The Fluid Mechanics of Microdevices—The Freeman Scholar Lecture,” Journal of Fluids Engineering, vol. 121, pp. 5–33.

Sen, M., Wajerski, D., and Gad-el-Hak, M. (1996) “A Novel Pump for MEMS Applications,” Journal of Fluids Engineering, vol. 118, pp. 624–627.

Gad-el-Hak, M., and Bandyopadhyay, P.R. (1994) “Reynolds Number Effects in Wall-Bounded Flows,” Applied Mechanics Reviews, vol. 47, pp. 307–365.