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High-Order Discontinuous Galerkin Method for Entry Simulations into Dusty Atmospheric Environments

AMS Seminar Series

Speakers: Matthias Ihme and Eric Ching, Stanford University

Presentation

Seminar Slide Deck (PDF-34MB)

Abstract

In recent years, the discontinuous Galerkin method has gained considerable interest, due to high-order accuracy with a compact stencil, geometric flexibility, suitability for high-performance computing paradigms, and other benefits. However, compared to more mature numerical schemes, it currently lacks a well-established infrastructure for handling complex multiphysics applications. In light of this issue, this work presents advancements to the discontinuous Galerkin scheme for simulating high-speed disperse multiphase flows. A simple and robust shock capturing method is first introduced. Intra-element variations are used to detect shocks, and smooth artificial viscosity is employed for stabilization. Quantitative comparisons with FUN3D and LAURA demonstrate that the proposed formulation can obtain accurate surface heating predictions in hypersonic flows with significantly less sensitivity to mesh-shock misalignment than finite volume techniques. An algorithmic framework for handling particle-laden flows is then discussed. The proposed algorithms are designed to track particles, account for fluid-particle interphase coupling, and treat particle-particle collisions on curved, high-aspect-ratio elements in an efficient and robust manner. The developed Euler-Lagrange methodology is applied to hypersonic particle-laden flows over blunt bodies, with Mars atmospheric entry as the target application. Experimental validation efforts and parametric sensitivities are discussed, followed by computations of hypersonic dusty flows over the full-scale ExoMars Schiaparelli capsule.

Biography

Photo of Matthias Ihme
Matthias Ihme is Associate Professor in Mechanical Engineering at Stanford University. He holds a BSc. degree in Mechanical Engineering and a MSc. degree in Computational Engineering. In 2008, he received his Ph.D. in Mechanical Engineering from Stanford. His research interests are broadly on the computational modeling of reacting flows, the development of numerical methods, and the investigation of advanced combustion concepts.

Photo of Eric Ching
Eric Ching is a PhD-candidates in the Mechanical Engineering Department at Stanford University. He obtained his BSc-degree in 2015 from Cornell and his research is concerned with the development of high-order discontinuous Galerkin methods and computational algorithms for predicting hypersonic and multiphase flows for simulating atmospheric entry into Martian environments. He has been collaborating with the NASA EDL-team and with DLR on the computational modeling and validation. He is recipient of a Stanford Graduate Fellowship, a Merrill Presidential Scholarship, and the McManus Design Award.