Split-Step Simulations to Assess the Effects of Atmospheric Boundary Layer Turbulence on the Dose Variability of N-Waves and Shaped Booms

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 …

DARPA Director’s Fellow

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 …

A simplified semi-empirical model for long-range low-frequency noise propagation in the turbulent atmosphere

My student, Dr. Tianshu Zhang, and myself recently published a modified long range acoustic propagation model that handles turbulence in the atmosphere. The abstract is We present a semi-empirical long-range low-frequency acoustic propagation model, which accounts for atmospheric turbulence. Ostashev and Wilson’s scattering model is combined with a ray-theory based refraction model to account for …

Chairing Turbulence Theory at APS Division of Fluid Dynamics – Highlight of the year

All our presenters were present and traveled internationally. DNS is the tool of choice for numerical simulations. Theory emerged from results, and I hope that new relations will guide those making turbulence models today. High-order inertial range scaling exponents in incompressible turbulence using generalized extended self-similarityPresenter: Sualeh Khurshid, Massachusetts Institute of Technology, Author: Sualeh Khurshid, …

APS Presentation – Alternative Analytical Solution for Planar Oblique Shock Waves

Abstract: One now famous analytical solution for shock waves was developed by Dr. Theodore Meyer within his Ph.D. dissertation under advisement of Professor Ludwig Prandtl. The original solution relies on analysis via control volume of the equations of motion. This approach has limited future development of analytical solutions for more complex flow-fields. In this presentation, …

The prediction of cross-spectra from first mode instability waves within high-speed flow over sharp and blunt cones with plasma actuation

Abstract: Leading edge geometries, such as cones, moving at high-speed undergo intense loading due to the growth of instability waves and turbulent transition. These instability waves are highly spatially coherent. Aerodynamic loading related to instability waves and transition cause large-amplitude vibrations within the underlying structure, which may lead to flight-vehicle failure. We examine the effect …

On Challenges in Turbulent Flow Theory and Experiment

Research in macroscopic classical physics, such as fluid dynamics or aspects of condensed matter physics, continues to confront baffling challenges that are by no means less demanding than those at the post-Newtonian frontiers of physics that have been explored since the beginning of this century. This is so even though the basic equations of macroscopic …

Standard k-Epsilon Model

In the last few years a number of models of turbulent heat and momentum transport have been developed in which the effective transport coefficients are related to local values of certain turbulent correlations; these correlations are computed simultaneously with the mean field variables. Models of this kind achieve significantly greater breadth of applicability than do …