Hypersonic Flow Past an Open Cavity Using HPC and Open-Source Software

Simulating hypersonic flow presents many computational challenges and requires use of software that can handle a wide range of external conditions. In general, hypersonic flight occurs at high altitude with flow regimes from the continuum, where the conventional no-slip boundary condition is appropriate, through to the free molecular regime, where the molecules no longer collide. This requires quite distinct software to handle the disparate flow regimes. In this research, we are using an in-house solver, ASTR, which is a high-order finite difference code suitable for continuum problems (altitudes below 70km), and a direct simulation Monte Carlo code, SPARTA, which is suitable for rarefied flows.Both codes are open-source and are very well suited to HPC. We are applying these codes to simulate hypersonic flow (Mach 6.9) past an open cavity (length-to-depth ratio of 2) at altitudes up to 120km.