Disturbance waves evolvement influenced by shock-boundary interaction

Both linear stability theory(LST) and direction numerical simulations(DNS) are used to study the instability of a shock-boundary interference flow at Ma= 4.5.An oblique shock wave was imposed on the two dimensional laminar flow,and a separation bubble forms between the shock wave and the solid plane,which causes compressing waves,expansion waves and vortex flows.TS waves were imposed on the flow at the upstream entrance.The evolution of the TS waves changed largely because of the complicated shock-boundary flow.In account of the shock wave,the separation region etc,analysis was made by studying the development of the evolved TS waves(include the by-generated waves).DNS results show that shock wave is different from compressing waves,and its effect to the small disturbance wave is quite different.DNS results also show that the separation region acts as a stability part.