High-Order Solution Methods for Aerothermodynamic Flow Simulations on Unstructured Meshes

Hypersonic vehicles have seen renewed interest in recent years for both civilian and government applications. However, the hypersonic flow regime poses unique challenges to computational aerothermodynamic simulation tools due to complex physics, including a combination of strong shockwave formation, thin boundary layers, real gas effects, thermochemical nonequilibrium, and departures from continuum flow at high altitudes. One of the primary challenges is prediction of surface heat transfer, which exhibits strong sensitivities to shock-induced instabilities, and errors that propagate to the thermal boundary layer. Current simulation tools impose strict requirements for spatial and temporal discretization of the domains to obtain sufficient accuracy and precludes automation of preprocessing and analyses. In this effort, CFD Research and Stanford University will develop and demonstrate a high-order Discontinuous Galerkin flow solver including nonequilibrium thermochemistry models and state-of-the-art shock capturing methods to significantly advance aerothermodynamic prediction capabilities for hypersonic flows. The developed capabilities will be verified and benchmarked against established finite-volume hypersonic flow solvers on planetary reentry test problems. Parallel scalability and performance will be benchmarked. The solver will be made available to NASA in an open-source manner and deployed on the NASA HPC platforms for ready utilization to support Human Landing Systems and other projects under the Mars exploration program.