Characterization of Hypersonic Instabilities over a Double Cone

Hypersonic flows over a double cone with unit Reynolds numbers of 9.35 × 10⁴ and 3.74 × 10⁵ m⁻¹ at a Mach number of approximately 16 were investigated using the continuum nonequilibrium SU2-NEMO solver. Close comparisons were made with previous DSMC findings for the first time, employing an axisymmetric configuration. It was observed that the SU2-NEMO framework reproduces both the measured data and the previously observed two-dimensional shear layer instabilities. To characterize the impact of three-dimensional instabilities, 3-D calculations were performed for both lower and higher Re cases. In the case of the lower Re, both 2-D and 3-D results were found to be essentially the same. However, for the higher Re case, the influence of spanwise instabilities was distinctive. Furthermore, the study marked the first investigation into the interaction of Kelvin-Helmholtz with spanwise instabilities.