The Johnson King turbulence model represented a significant advancement in the understanding and modeling of turbulent flows. Introduced amidst the exploration of first and second equation models, the Johnson King model distinguished itself through the innovative concept of a half-equation model, emphasizing the critical role of memory in turbulence phenomena. The early stages of turbulence …
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It has been approximately twenty years since Professor Olga Alexandrovna Ladyzhenskaya passed away. An eminent mathematician and member of several Academies of Science, passed away in January 2004. Her distinguished career was marked by significant contributions to partial differential equations, particularly the Navier–Stokes equations and nonlinear elliptic and parabolic equations. Born in 1922 in Kologriv, …
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I completed my Acoustical Society work and returned to the United States. Abstract: An analytical closed-form solution is presented for the aerodynamic near-field and ground signature from an axisymmetric body with a low thickness ratio. The Navier-Stokes equations are formulated as a boundary value problem that incorporates the incoming ambient flow-field and the aerodynamic properties …
https://everloved.com/life-of/stephen-jurczyk/obituary/ It seems just like yesterday that I was at NASA Langley working for a short time under then Director Stephen G. Jurczyk. He passed away just recently on Thanksgiving of 2023. He helped propel my career in the later stages of my time at Langley. One thing that I appreciated a lot about Stephen …
Appearing next month in the NASA Alumni Newsletter. Walking on the Washington, D.C. Mall is an inspiring experience for all citizens. One might be inspired by the many memories and great institutions of our American people. Nestled as one of the most visited museums of the world is the National Air and Space Museum, just …
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My former student, Dr. Alex Carr, along with Dr. J. Lonzaga, who are both of NASA Langley Research Center, and myself published an article on the propagation of sonic boom through the turbulent atmosphere. Abstract: The effects of atmospheric boundary layer turbulence on the loudness variability of a sonic boom N-wave and shaped boom are …
Who would have thought that 7 years go by so quickly at the University of Florida. This year I am teaching introduction to computational fluid dynamics. The last time I taught it was before COVID in the fall of 2020. I am working on a new design program for nozzles. I am basing it on …
I am very fortunate to be awared the 2023-2024 DARPA Director’s Fellowship. The linked article from my department is at the following link: https://mae.ufl.edu/2023/08/09/darpa-directors-fellowship-awarded-to-steven-a-e-miller/ The article text is below Associate Professor Steven A. E. Miller, Ph.D., is awarded the Director’s Fellowship from the Defense Advanced Research Projects Agency (DARPA) for 2023-2024. The award recognizes technical …
Abstract: Hypersonic flight-vehicles create shock and expansion waves that propagate through the atmosphere and are observed on the ground as sonic booms. We present a methodology to predict the near-field aerodynamic pressure and sonic boom signature using approximately 1% of the computational cost relative to fully-nonlinear computational fluid dynamics and state-ofthe-art sonic boom propagation solvers. …
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Graduate Student Garrison S. Osborne and Steven A. E. MillerUniversity of Florida Department of Mechanical and Aerospace Engineering Well before the loss of Columbia, the NASA Office of Technology Assessment wrote, “Shuttle reliability is uncertain, but has been estimated to range between 97 and 99 percent. If the Shuttle reliability is 98 percent, there would …
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