Adaptive Mesh Refinement Disturbance Flow Tracking Applied to Hypersonic Boundary Layer Transition Prediction

Speaker: Vincenzo Russo, University of Kentucky
May 4, 2023

Presentation

Abstract

Direct Numerical Simulation (DNS) has been extensively used as tool for boundary layer stability investigations and can in principle be used for all stages of the boundary layer transition process as well as for fully turbulent flows. Nevertheless, the computational cost of transitional flows simulations over realistic vehicle configurations is extremely high; hence, the use of DNS for practical applications is limited. The Adaptive Mesh Refinement Wave-Packet Tracking (AMR-WPT) method has been developed as an efficient alternative to conventional DNS, and if combined with an Immersed Boundary Method (IBM) can offer a high degree of flexibility, especially when treating complex geometries, with extremely limited set-up time (especially during the grid generation phase). This presentation will detail the AMR-WPT method and its application to a wide range of boundary layer transition problems, including particle-induced transition, transition on a finned cone and BOLT. When applied to hypersonic flows, it will be demonstrated that the AMR-WPT-IBM can be employed for tracking first and second mode instabilities with dramatically greater computational efficiency when compared to conventional approaches. Recent research efforts have demonstrated the capabilities of the AMR-WPT-IBM approach to efficiently simulate particle-induced transition as well as different types of instabilities (e.g., vortical modes) developing on complex geometries (like finned cones and BOLT). The presentation will highlight some interesting flow physics that have been simulated with this approach, e.g., the observation of the transition growth mechanism through particle impingement, as well as comparisons with other transition prediction methods.

Biography

Vincenzo Russo completed his Research Master at the von Karman Institute for Fluid Dynamics, after being awarded a NATO scholarship to study at the Institute. During his Master's degree he had the opportunity to develop and test adjoint and gradient based techniques for aerodynamic optimization. He spent a short period of time in industry working as consultant for Rolls-Royce and Airbus, and he is currently a Ph.D. candidate in Mechanical and Aerospace Engineering at the University of Kentucky, under the supervision of Professor C. Brehm (University of Maryland). His current research focuses on hypersonic boundary layer transition and numerical method development for efficient transition prediction.

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