Asymmetric shock reflection in supersonic overexpanded jet

This paper investigates asymmetric shock reflection in a supersonic overexpanded jet. A theoretical model that can predict the size and shape of flow field structures such as shocks, expansion waves and sliplines is established. For symmetric Mach reflection, the current model exhibits better agreement with numerical simulation results. For asymmetric Mach reflection, the current model also shows good agreement with numerical simulation results in predicting Mach stem height. The research indicates that the Mach stem height decreases with increasing nozzle pressure ratio and nozzle exit length difference, and decreases as the nozzle exit Mach number decreases. In addition, the critical geometric condition for complete misalignment of the upper and lower slipline interference segments (i.e. when the interference between one side of the expansion wave and the slipline ends, the other side of the expansion wave has not yet begun to interfere with the slipline) is given, which increases approximately linearly with nozzle pressure ratio and decreases as the nozzle exit Mach number increases. This study provides important theoretical support for the engineering application of asymmetric shock reflection in supersonic overexpanded jet.