"X"布局高超声速倒置进气道激波与附面层干扰

Suppression of Interaction Between Shock Wave and Boundary Layer for "X" Hypersonic Inverted Inlet

关键词:  高超声速倒置进气道  激波与附面层干扰  分流楔  数值仿真  冲压发动机

Key words:  Hypersonic inverted inlet  Shock wave/boundary layer interaction  Diverter  Numerical simulation  Ramjet engine

摘要:

采用标准k-ω SST湍流模型数值计算方法，针对二元高超声速倒置进气道激波与附面层严重的干扰现象，采用分流楔抑制激波与附面层干扰方法，对有无分流楔的进气道性能及流动机理特征进行了详细的研究。结果表明:采用分流楔的流动控制方法，有效抑制了激波/附面层产生的分离包对进气道内流动的干扰；提高倒置进气道的气动性能，进气道的总压恢复系数和流量捕获系数均有提高，计算模型的壁面总阻力系数得到一定程度的减小。数值计算结果表明，在分流楔尾迹中强剪切流动在一定程度上缓解了激波与附面层干扰的强度；在分流楔后缘存在稳定的横向涡，由于气流进入尾迹驻涡是来自附面层外的总压较高的高能流体，提高了附面层的抗逆压能力；由于尾迹驻涡的存在使得分离涡没有向弹体周向扩散，减小了阻力。该方法实现了对高超声速倒置进气道激波/附面层干扰的抑制，揭示了其抑制的机理。

Abstract:

Aiming at suppression of shock wave and boundary layer interaction in two dimensional hypersonic inverted inlet，numerical simulation based on turbulent k-ω SST was performed. A suppression method was adopted to reduce the effects of the interaction shock wave and boundary layer of missile body based on the flow diverter. Inlet performance was compared and flow mechanism was studied with diverter and without diverter. Computational results indicate that the separation was suppressed with diverter，and the performance of inlet aerodynamic was improved effectively by means of this suppression method. Both the total pressure recovery coefficient and the flow coefficient of inlet increase while total drag coefficient for the wall slightly decreases. This is due to the fact that the intensity of the shock wave/ boundary layer interaction behind the diverter was reduced by the strong shear layer flow. In addition，stable transverse vortex behind the diverter is formed. It can be clearly seen that the fluid in the trail vortex is from the flow above the diverter with higher total pressure so that the capability in the transverse vortex on resisting back pressure is enhanced. Meanwhile，the flow suppression is extended along circumferential direction without diverter and this happens with diverter . This partially contributes to the reduction of drag coefficient. Based on results obtained and its mechanism analysis，it can be concluded that this method can be considered to be effective for suppression of the interaction between the shock wave and boundary layer for hypersonic inverted inlet and its suppression mechanism has been revealed.