激波边界层的相互作用对扰动波传播的影响

利用线性稳定性理论和直接数值模拟研究了带有入射斜激波的、来流马赫数Ma=4．5条件下的平板边界层的失稳特性。重点考察了在由于激波边界层相互干扰，平板边界层上形成分离区，又进而产生激波、膨胀波和旋涡等复杂流动现象的流场上游，引入小扰动的TS波后，扰动波传播通过带有这些复杂流动现象的流场时，扰动波的发展变化特点。通过对流场中扰动波（包括基本波和衍生波）演化特征的分析，研究分离和激波等复杂流动现象对平板边界层稳定性的影响特点。数值模拟发现，激波的出现不同于一般的压缩波，在亚声速区与超声速区对扰动波演化的影响是不同的，此外，分离对扰动有稳定作用。

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.