三级压缩楔前缘半径对壁面静压及热流分布影响研究

Research on Leading Edge Radius Effect on Wall Static Pressure and Heat Flux Distribution of Three-Stage Compression Ramp

关键词:  压缩楔  前缘半径  壁面静压  壁面热流  激波边界层干扰  高超声速进气道

Key words:  Compression ramp  Leading edge radius  Wall static pressure  Wall heat flux  Shock wave boundary layer interaction  Hypersonic inlet

摘要:

为了研究三级压缩楔前缘半径对壁面静压和热流分布的影响，在0.6m激波风洞上开展了试验测量，模型长约0.6m，前缘半径为0mm～3mm，试验名义马赫数为5.98。研究结果表明，试验得到的壁面静压和热流数据重复性很好。采用Fluent软件进行了二维和三维流场参数辅助模拟分析，三种不同湍流模型获得的壁面静压分布差别不大，均与试验结果吻合较好；不同湍流模型获得的壁面热流分布差异较大，采用标准k-ε模型得到的结果与试验吻合较好。试验和数值模拟结果均表明，在第二和第三压缩面上，经过激波后，壁面静压逐渐上升到一个压强平台；壁面热流逐渐上升到一个局部极大值，然后在同一压缩面持续下降。随前缘半径增加，壁面静压和壁面热流整体减小，压强平台值和热流局部极大值也减小，而达到压强平台和热流局部极大值需要的长度增加，显示激波边界层干扰影响区域增大。

Abstract:

In order to study the effects of leading edge radius on three-stage ramps wall static pressure and heat flux distribution，the experimental work is carried out in 0.6m shock tunnel of CARDC at Ma=5.98. The total length of the test models compression surfaces is about 0.6 meter，with the radius of the leading edge 0～3mm. The wall static pressure and heat flux data are quite repetitious in duplicated test. Two and three dimensional flow field parameters were obtained by FLUENT，and it shows that the wall static pressure by three different viscous models are similar，and all of which are coincident with experiment results. The wall heat flux is different by different viscous models，and the results by standard k-ε model are best coincident with experiment results. The results from experiment and CFD show that wall static pressure increases gradually downstream shockwave reaching a pressure platform on the second and third compression surfaces，while heat flux increases gradually downstream shockwave reaching a local maximum，and then decreases gradually on the compression surface. With the leading edge radius increasing，the value of pressure platform and heat flux local maximum becomes lower，and the length reaching pressure platform and heat flux local maximum becomes longer，which shows that the shock wave boundary layer interaction region extends.