John Steinhoff

Last updated
John Steinhoff
Born (1942-09-15) September 15, 1942 (age 79)
Nationality United States
Known forVorticity Confinement method
Scientific career
Fields Physics
Institutions University of Tennessee Space Institute

John Steinhoff (15 September 1942 ) is a classical physicist, best known for his important contributions to computational fluid dynamics field. He invented a physics based method called vorticity confinement to compute the numerical solution of partial differential equations.

Biography

Steinhoff studied at University of Chicago where he was awarded a M.S. degree in physics. Later, in 1972, University of Chicago awarded him with a Ph.D. degree. He later held a faculty position in the department of aerospace engineering, University of Tennessee Space Institute from 1981 to 2011. [1]

Most of his research has been involved the treatment of vortex-dominated flows in computational fluid dynamics and the treatment of short wave equation pulses, including the solution of real problems of engineering importance. The recent development of the vorticity confinement method that eliminates effects of numerical diffusion, for computations on Eulerian grids, without the use of Lagrangian markers. This technique has recently been used in many applications involving computation of: Helicopter Blade—Vortex Interaction, Delta Wing Flow, Helicopter Rotor/Body Flow, Helicopter Body—Vortex Interaction, Dynamic Stall, Aircraft Trailing Vortices, Supersonic Flow Over Missiles. Steinhoff also developed another computational technique, wave confinement, for propagating short wave equation pulses over long distances without the use of Lagrangian markers, which require the use of complex logic and are not feasible for intersecting pulses. This has major applications in communications, radar wave scattering, etc. His methods have also been used in creating special effects for movies such as Harry Potter and The Core.[ citation needed ]

He also authored many scholarly articles and chapters on Vorticity Confinement. He was awarded the Arnold Research award for his major accomplishments in CFD field.

Related Research Articles

In continuum mechanics, vorticity is a pseudovector field that describes the local spinning motion of a continuum near some point, as would be seen by an observer located at that point and traveling along with the flow. It is an important quantity in the dynamical theory of fluids and provides a convenient framework for understanding a variety of complex flow phenomena, such as the formation and motion of vortex rings.

Computational fluid dynamics Analysis and solving of problems that involve fluid flows

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Fluid–structure interaction

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Bram van Leer

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Alexandre Chorin American mathematician

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Vorticity confinement (VC), a physics-based computational fluid dynamics model analogous to shock capturing methods, was invented by Dr. John Steinhoff, professor at the University of Tennessee Space Institute, in the late 1980s to solve vortex dominated flows. It was first formulated to capture concentrated vortices shed from the wings, and later became popular in a wide range of research areas. During the 1990s and 2000s, it became widely used in the field of engineering.

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Fluid motion is governed by the Navier–Stokes equations, a set of coupled and nonlinear partial differential equations derived from the basic laws of conservation of mass, momentum and energy. The unknowns are usually the flow velocity, the pressure and density and temperature. The analytical solution of this equation is impossible hence scientists resort to laboratory experiments in such situations. The answers delivered are, however, usually qualitatively different since dynamical and geometric similitude are difficult to enforce simultaneously between the lab experiment and the prototype. Furthermore, the design and construction of these experiments can be difficult, particularly for stratified rotating flows. Computational fluid dynamics (CFD) is an additional tool in the arsenal of scientists. In its early days CFD was often controversial, as it involved additional approximation to the governing equations and raised additional (legitimate) issues. Nowadays CFD is an established discipline alongside theoretical and experimental methods. This position is in large part due to the exponential growth of computer power which has allowed us to tackle ever larger and more complex problems.

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References

  1. "John Steinhoff" . Retrieved 5 July 2022.