Application of Metric-Based Anisotropic Mesh Adaptation to 3D High-Speed Compressible Flows

This work demonstrates the numerical benefits of metric-based anisotropic mesh adaptation for viscous, hypersonic flow simulations, utilizing the scalable, computational fluid dynamics (CFD) solver developed at the US Department of Energy's Oak Ridge National Laboratory (ORNL), NASA's refine, and the Engineering Sketch Pad (ESP) with the pyCAPS module. First, this work investigates four scalar fields for the Hessian-based multiscale metric through a code-to-code benchmark on the Mach 5.0 `Blottner sphere'. The scalar field selected from this code benchmark is then evaluated on a much higher Mach-number flow, namely the Mach 17.605 `Gnoffo’ sphere, to assess the robustness and effectiveness of the mesh adaptation strategy in an extreme hypersonic regime. Finally, the numerical predictions of shock separation in a Mach 7.2 double cone are validated against experimental data from the University of Texas at San Antonio (UTSA) Mach 7.2 Ludwieg Tube. Both code benchmark and experimental validation results underscore the effectiveness of anisotropic metric-based mesh adaptation in accurately capturing key flow features and predicting flow quantities of interest with fewer mesh elements than static-grid simulations and less user interaction in the mesh generation process.