Investigation of the Unsteady Edney Type IV and VII Shock–Shock Interaction

Edney type IV and type VII shock-shock interactions are complex hypersonic flow phenomena. They are characterized by a supersonic jet which reaches far into the flow field. An experimental investigation of the inner jet structure is difficult, especially in cases where the jet is subject to high-frequency unsteady movements. The present paper provides insight into the jet structure by means of a highly-resolved Computational Fluid Dynamics analysis in thermochemical nonequilibrium. Simulations of an Edney type IV interaction in nitrogen flow are presented. Multiple resolution levels support the identification and analysis of the mechanisms of the jet unsteadiness. The second configuration is an Edney type VII interaction. This shock-shock interaction type was observed and defined in nitrogen flow by Yamamoto et al. The present results demonstrate that this interaction may also be observed in CO 2-dominated flow with a gas composition similar to the Martian atmosphere. The results provide insight into the jet structure of this less known interaction.