锯齿形转捩片触发高超声速进气道边界层转捩的大涡模拟

为促进锯齿形转捩片在高超声速进气道中的应用，以地面风洞条件下的二元进气道为研究对象，采用高精度大涡模拟方法对锯齿形转捩片在三级压缩楔面上触发的边界层转捩现象开展了研究。数值方法基于隐式亚格子模型，空间离散采用高精度通量限制型紧致格式，时间推进采用显式Runge-Kutta方法。数值模拟清晰捕捉到了边界层转捩的空间发展演化过程，并获得了统计平均流场以及流场脉动特征。数值模拟结果表明转捩片能够有效触发进气道压缩面边界层转捩；通过与等熵压缩面及单楔面数值模拟结果的对比分析，获得了转捩片触发边界层转捩的内在机理，为后续研究工作奠定了基础。

Large eddy simulation of hypersonic inlet boundary layer transition triggered by zig-zag trip

To promote the application of zig-zag trip in hypersonic inlet, a high-precision large eddy simulation method is used to examine the boundary layer transition triggered by zig-zag trip on three-stage compression wedge of two-dimensional inlet in wind tunnel. The numerical method is based on the implicit subgrid-scale model. The high-precision flux-limited compact scheme is used for spatial discretization and the explicit Runge-Kutta method for time marching. The numerical simulation clearly captures the spatial evolution process of boundary layer transition, and obtains the statistical mean flow field and fluctuation characteristics. The numerical simulation results show that the zig-zag trip can effectively trigger the boundary layer transition. By comparing the numerical simulation results with those of isentropic compression surface and single wedge surface, the mechanism of boundary layer transition is obtained and lays a foundation for further study.