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Mujeeb R. Malik is a Pakistani born American aerospace engineer serving as Senior Aerodynamicist at NASA Langley Research Center. He is known for his research in boundary layer stability, laminar-turbulent transition, computational methods and aerodynamic simulations. He was the architect of CFD Vision 2030, [1] a NASA-sponsored study to advance the state-of-the-art of computational fluid dynamics (CFD) by exploiting high performance computing and modern validation experiments .
Malik received his bachelor's degree from University of Engineering and Technology, Lahore, in 1973. He received his master's degree from University of Toronto, Canada and Ph.D. from Iowa State University in 1978, where he specialized in computational fluid dynamics and heat transfer. He was President and Chief Scientist of High Technology Corporation, a research & development company he founded. At NASA, he served as the Head of Computational Aerosciences Branch before being elevated to Senior Technologist (ST), technical equivalent of the Senior Executive Service.
In 2008, Malik was awarded the status of Fellow in the American Physical Society, after he was nominated by their Division of Fluid Dynamics, for pioneering contributions to the understanding of the breakdown of crossflow vortices in three-dimensional boundary layers, attachment-line and hypersonic boundary layer instability including real gas effects, and developing physics-based methods for the prediction of laminar-turbulent transition. He was elected Fellow of American Institute of Aeronautics and Astronautics, AIAA, in 2009, for notable contributions made to the arts, sciences, and technology of aeronautics and astronautics. in 2012, NASA presented him the Exceptional Service Medal, for distinguished supervisory and technical leadership for the advancement for aerodynamic technologies and their impact on Agency missions. He received NASA's Silver Achievement Medal in 2018, for excellence, teamwork and technical leadership in developing a path to revolutionary computational fluid dynamics for aerosciences. Malik is also a Fellow of American Society of Mechanical Engineers.
Aerodynamics is the study of the motion of air, particularly when affected by a solid object, such as an airplane wing. It involves topics covered in the field of fluid dynamics and its subfield of gas dynamics, and is an important domain of study in aeronautics. The term aerodynamics is often used synonymously with gas dynamics, the difference being that "gas dynamics" applies to the study of the motion of all gases, and is not limited to air. The formal study of aerodynamics began in the modern sense in the eighteenth century, although observations of fundamental concepts such as aerodynamic drag were recorded much earlier. Most of the early efforts in aerodynamics were directed toward achieving heavier-than-air flight, which was first demonstrated by Otto Lilienthal in 1891. Since then, the use of aerodynamics through mathematical analysis, empirical approximations, wind tunnel experimentation, and computer simulations has formed a rational basis for the development of heavier-than-air flight and a number of other technologies. Recent work in aerodynamics has focused on issues related to compressible flow, turbulence, and boundary layers and has become increasingly computational in nature.
In physics, physical chemistry and engineering, fluid dynamics is a subdiscipline of fluid mechanics that describes the flow of fluids—liquids and gases. It has several subdisciplines, including aerodynamics and hydrodynamics. Fluid dynamics has a wide range of applications, including calculating forces and moments on aircraft, determining the mass flow rate of petroleum through pipelines, predicting weather patterns, understanding nebulae in interstellar space and modelling fission weapon detonation.
In physics, a shock wave, or shock, is a type of propagating disturbance that moves faster than the local speed of sound in the medium. Like an ordinary wave, a shock wave carries energy and can propagate through a medium but is characterized by an abrupt, nearly discontinuous, change in pressure, temperature, and density of the medium.
A magnetohydrodynamic drive or MHD accelerator is a method for propelling vehicles using only electric and magnetic fields with no moving parts, accelerating an electrically conductive propellant with magnetohydrodynamics. The fluid is directed to the rear and as a reaction, the vehicle accelerates forward.
Computational fluid dynamics (CFD) is a branch of fluid mechanics that uses numerical analysis and data structures to analyze and solve problems that involve fluid flows. Computers are used to perform the calculations required to simulate the free-stream flow of the fluid, and the interaction of the fluid with surfaces defined by boundary conditions. With high-speed supercomputers, better solutions can be achieved, and are often required to solve the largest and most complex problems. Ongoing research yields software that improves the accuracy and speed of complex simulation scenarios such as transonic or turbulent flows. Initial validation of such software is typically performed using experimental apparatus such as wind tunnels. In addition, previously performed analytical or empirical analysis of a particular problem can be used for comparison. A final validation is often performed using full-scale testing, such as flight tests.
The Kelvin–Helmholtz instability is a fluid instability that occurs when there is velocity shear in a single continuous fluid or a velocity difference across the interface between two fluids. Kelvin-Helmholtz instabilities are visible in the atmospheres of planets and moons, such as in cloud formations on Earth or the Red Spot on Jupiter, and the atmospheres of the Sun and other stars.
Fluid mechanics is that branch of physics concerned with the mechanics of fluids and the forces on them. It has applications in a wide range of disciplines, including mechanical, aerospace, civil, chemical, and biomedical engineering, as well as geophysics, oceanography, meteorology, astrophysics, and biology.
In fluid dynamics, turbulence modeling is the construction and use of a mathematical model to predict the effects of turbulence. Turbulent flows are commonplace in most real-life scenarios. In spite of decades of research, there is no analytical theory to predict the evolution of these turbulent flows. The equations governing turbulent flows can only be solved directly for simple cases of flow. For most real-life turbulent flows, CFD simulations use turbulent models to predict the evolution of turbulence. These turbulence models are simplified constitutive equations that predict the statistical evolution of turbulent flows.
The Advection Upstream Splitting Method (AUSM) is a numerical method used to solve the advection equation in computational fluid dynamics. It is particularly useful for simulating compressible flows with shocks and discontinuities.
Fluid–structure interaction (FSI) is the interaction of some movable or deformable structure with an internal or surrounding fluid flow. Fluid–structure interactions can be stable or oscillatory. In oscillatory interactions, the strain induced in the solid structure causes it to move such that the source of strain is reduced, and the structure returns to its former state only for the process to repeat.
Bram van Leer is Arthur B. Modine Emeritus Professor of aerospace engineering at the University of Michigan, in Ann Arbor. He specializes in Computational fluid dynamics (CFD), fluid dynamics, and numerical analysis. His most influential work lies in CFD, a field he helped modernize from 1970 onwards. An appraisal of his early work has been given by C. Hirsch (1979)
In fluid dynamics, drag crisis is a phenomenon in which drag coefficient drops off suddenly as Reynolds number increases. This has been well studied for round bodies like spheres and cylinders. The drag coefficient of a sphere will change rapidly from about 0.5 to 0.2 at a Reynolds number in the range of 300000. This corresponds to the point where the flow pattern changes, leaving a narrower turbulent wake. The behavior is highly dependent on small differences in the condition of the surface of the sphere.
Mohammed Yousuff Hussaini is an Indian born American applied mathematician. He is the Sir James Lighthill Professor of Mathematics and Computational Science & Engineering at the Florida State University, United States. Hussaini is also the holder of the TMC Eminent Scholar Chair in High Performance Computing at FSU. He is widely known for his research in scientific computation, particularly in the field of computational fluid dynamics (CFD) and Control and optimization. Hussaini co-authored the popular book Spectral Methods in Fluid Dynamics with Claudio Canuto, Alfio Quarteroni, and Thomas Zang. He is the editor-in-chief of the journal Theoretical and Computational Fluid Dynamics.
In fluid dynamics, the process of a laminar flow becoming turbulent is known as laminar–turbulent transition. The main parameter characterizing transition is the Reynolds number.
Dimitris Drikakis, PhD, FRAeS, CEng, is a Greek-British applied scientist, engineer and university professor. His research is multidisciplinary. It covers fluid dynamics, computational fluid dynamics, acoustics, heat transfer, computational science from molecular to macro scale, materials, machine learning, and emerging technologies. He has applied his research to diverse fields such as Aerospace & Defence, Biomedical, and Energy and Environment Sectors. He received The William Penney Fellowship Award by the Atomic Weapons Establishment to recognise his contributions to compressible fluid dynamics. He was also the winner of NEF's Innovator of the Year Award by the UK's Institute of Innovation and Knowledge Exchange for a new generation carbon capture nanotechnology that uses carbon nanotubes for filtering out carbon dioxide and other gases.
Skin friction drag is a type of aerodynamic or hydrodynamic drag, which is resistant force exerted on an object moving in a fluid. Skin friction drag is caused by the viscosity of fluids and is developed from laminar drag to turbulent drag as a fluid moves on the surface of an object. Skin friction drag is generally expressed in terms of the Reynolds number, which is the ratio between inertial force and viscous force.
Robert Lafayette Ash is a Professor of Mechanical & Aerospace Engineering and an Eminent Scholar at Old Dominion University in Norfolk, Virginia.
Kazimierz R. Czarnecki was an aeronautics engineer who worked for the National Advisory Committee for Aeronautics, and later, for the National Aeronautics and Space Administration.
A bypass transition is a laminar–turbulent transition in a fluid flow over a surface. It occurs when a laminar boundary layer transitions to a turbulent one through some secondary instability mode, bypassing some of the pre-transitional events that typically occur in a natural laminar–turbulent transition.
Reda R. Mankbadi is the founding Dean of the Engineering College at Embry-Riddle Aeronautical University. He is a former NASA senior scientist at NASA's Glenn Research Center and a Fellow of the NASA Lewis Research Academy. Mankbadi has published over 150 scientific papers.