Economical Third-Order Methods for Accurate Surface Heating Predictions on Simplex Element Meshes

Kyle B Thompson; Hiroaki Nishikawa; Emmett Padway; Matthew D O'Connell

NASA NTRS · 20220017904

Economical Third-Order Methods for Accurate Surface Heating Predictions on Simplex Element Meshes

Kyle B Thompson·Hiroaki Nishikawa·Emmett Padway·Matthew D O'Connell

Abstract

A node-centered edge-based finite volume discretization of the compressible Navier-Stokes equations is presented with the heat flux reformulated as a first order system. A dissipation vector is derived for the reformulated system, such that the heat flux can be upgraded to O(h^3) on simplex element meshes in the same fashion as the inviscid fluxes. The method of manufactured solutions is used to demonstrate this uniform order property in heat flux. This new system is shown to efficiently produce accurate surface heating predictions on hypersonic hemisphere flow using an anisotropic simplex element mesh, achieving O(h^3) accuracy at relatively low computational cost compared to similar methods.

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BibTeX RIS

Kyle B Thompson, Hiroaki Nishikawa, Emmett Padway, Matthew D O'Connell. Economical Third-Order Methods for Accurate Surface Heating Predictions on Simplex Element Meshes. https://ntrs.nasa.gov/citations/20220017904

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