Numerical and experimental investigation of double-cone shock interactions

A series of experiments was conducted in the Princeton University Mach 8 Wi nd Tunnel to study shock interactions on axisymmetric double-cone geometrie s. Schlieren images and surface-pressure data were taken. Two models were t ested, which were expected to produce steady Type VI and Type V shock inter actions. The experiments are compared to computational fluid dynamics calcu lations, and the features of these complicated flowfields are discussed, Th e comparison is excellent for the laminar Type VI shock interaction. The co mputations accurately reproduce the size of the separation zone and the sur face pressure. However, for the Type V interaction the laminar computation overpredicts the size of the separation region. In addition, the experiment al results for the Type V interaction show that the size of the separation region decreases with increasing Reynolds number, whereas the laminar compu tations predict the opposite trend. Turbulent computations show much better agreement dth experimental data and reproduce the experimentally observed relationship between the size of the separation region and the Reynolds num ber, indicating that the reattachment shocks cause transition to turbulence in these flows.