Navier-stokes predictions of hypersonic double-cone and cylinder-flare flow fields

The interaction between a shock wave and a separated region in a hypersonic flow is a very challenging problem for computational fluid dynamics. Recent calculations on double-cone and hollow-cylinderflare geometries have shown significant differences between computations and experiments. Therefore, experiments have been performed in the Large Energy National Shock (LENS) facility at the Calspan - University at Buffalo Research Center (CUBRC) to provide a benchmark dataset at well calibrated hypersonic test conditions with fully laminar flow. These flows are test cases for the NATO Research and Technology Organization (RTO) Working Group 10 CFD code validation activities. In this paper, we discuss several parametric studies of these flows. We show that the experiments are not sensitive to small nosetip bluntness and slight model misalignment. We do not expect non-continuum effects or vibrational excitation to be significant in these flows. The calculations require grids of about a half million points, but more importantly, the results are very sensitive to the numerical flux evaluation method used. Finally, we present our results for two double-cone and hollow-cylinder with extended flare geometries for comparison with the experimental data.