超声速流中圆锥头部钝度对边界层稳定性的影响  

The bluntness effect on stability of boundary layer over blunt cone in supersonic flow

作　　者：闫溟[1] 罗纪生[1,2] 

机构地区：[1]天津大学力学系,天津300072 [2]南开大学天津大学刘徽应用数学研究中心,天津300072

出　　处：《空气动力学学报》2008年第4期430-434,共5页Acta Aerodynamica Sinica

基　　金：国家自然基金重点项目资助(批准号:10632050)

摘　　要：通过直接数值模拟,计算得到超声速流中各种钝度圆锥周围的流场情况。结果表明圆锥头部钝度增加,使边界层增厚,边界层向自由流的过渡变得更平缓。这种变化进而使流场稳定性发生改变,通过对流场进行线性稳定性分析发现,随着圆锥钝度增加,边界层中最先出现不稳定波的位置向后移动,临界雷诺数增加;流场中存在不稳定波的频带变窄,同时整体向低频方向移动;T-S波的不稳定频段向低频移动时,其增长率减小,不稳定特性减弱。Direct numerical simulation is used to get the stable flow fields over blunt cones which have different bluntness in supersonic flow. The result show that boundary layer thickness grows with bluntness. This can result in the change of boundary layer stability. By linear stability analysis we can get the following results： With increasing bluntness of the cone,the location where T-S wave first becomes unstable is moved rearward,as a result the critical Reynolds number grows, the unstable T-S wave frequency bandwidth reduces,and moves to the low-frequency side,with the movement,the unstable mechanism of the T-S wave decreases.

关 键 词：超声速 钝锥 边界层 稳定性 

分 类 号：O357.4[理学—流体力学]