The next big leap in aerospace propulsion currently aims at enabling high hypersonic (Mach 8-15) air-breathing propulsion. One such novel configuration is the Shock-induced Combustion Ramjet (Shcramjet) that leverages the high-Mach incoming air to perform extreme shock-based compression using obstacles such as a wedge that results in the formation of an "oblique detonation wave (ODW)" resulting in "detonative" combustion as opposed to the traditional "deflagration" combustion in aerospace engines. Detonation-based combustion is poised to yield much higher efficiencies and such engines also possess very little moving parts. However, designing such engines and stabilizing ODWs in experimental configurations becomes a great challenge due to the high costs associated with hypersonic wind-tunnel testing and the extremely small time available to collect data. In this work, we leverage Computational Fluid Dynamics (CFD) to capture intricate details of the ODW stabilization process and its associated flow features. The simulations reveal for the first time that ODWs possess a very complex structure with different zones of instabilities. Close to the wedge surface it is observed that the detonation is only "mildly" unstable whereas further downstream, a pair of a family of shock-waves begin to periodically squeeze very tiny locally "hypersonic" microjets that helps in sustaining the ODW for robust operation.
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