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Towards Fully-Resolved Particulate-Induced Transition Simulations for High-Speed Boundary-Layers with an Immersed Boundary Method

AMS Seminar Series

Speaker: Oliver M. F. Browne, University of Kentucky

Presentation

Seminar Slide Deck (PDF-42.5MB)

Abstract

This talk will present a numerical approach to model particulate-induced transition in the upper atmosphere (stratosphere) relevant for high-speed (high supersonic/hypersonic) vehicles. Various types of particulates with different origins and a wide range of properties are present in the stratosphere and could provide the threshold disturbance energy to cause boundary-layer transition. Atmospheric particulates impinging on the surface of high-speed vehicles trigger a wavepacket inside the boundary layer which, based on the flow and particle conditions, can grow substantially and provide a path to turbulence.

In the first part of this presentation, our newly developed wavepacket tracking strategy coupled with a particle model will be presented. The wavepacket tracking approach, namely AMR-WPT (adaptive mesh refinement wavepacket tracking), relies on (1) the nonlinear disturbance flow formulation of the compressible Navier-Stokes equations, (2) a dual mesh overset approach, and (3) adaptive mesh refinement (AMR). The AMR-WPT approach has been demonstrated to result in significant computational savings when compared to conventional approaches for transition prediction. To model particulate-induced transition, AMR-WPT was initially coupled with a particle solver based on the particle-in-cell (PIC) approach. The second part of this talk will present a higher-fidelity approach by modeling the particle with a higher-order Immersed Boundary Method (IBM) and coupling it with the AMR-WPT method. Both methods will be validated for typical hypersonic transition prediction test cases.

Biography

Photo of Oliver M. F. Browne
Oliver M. F. Browne is a Postdoctoral Research Associate in the Department of Mechanical Engineering at University of Kentucky. He was born and raised in Coulsdon, a town in London, England. He received his B.Eng. degree in Aerospace Engineering from Coventry University (UK) in 2011 and his M.Sc. in Aeronautics from Imperial College London (UK) in 2012. He received his Ph.D. (funded by a Marie Skłodowska-Curie Fellowship from the European Union) in Aerospace Engineering from Universidad Politécnica de Madrid (Spain) in May 2016. From September 2016 until August 2017, Oliver was a Postdoctoral Research Associate at University of Arizona but based at University of Kentucky as a Visiting Scholar. In August 2017, he became a Postdoc at the University of Kentucky, working for Dr. Christoph Brehm and working projects related to developing numerical methods for hypersonic boundary-layer transition prediction.