壁面函数在激波诱导分离流动中的应用

摘要

以数值模拟激波-附面层干扰引起的流动分离问题为研究背景，发展了基于有限体积方法的雷诺平均Navier-Stokes（RANS）方程的流场数值模拟方法。利用壁面函数模型得到壁面剪切应力，通过修正壁面粘性通量，构造了一种新的湍流边界处理方法，并将其耦合到RANS方程和SST k-ω湍流模型的数值求解中；同时，针对激波诱导引起的附面层流动分离问题，提出一种附面层网格加密技术，能够自适应加密分离区内附面层网格，使得在流动分离区域也能够使用壁面函数模型。数值算例表明，壁面函数模型能够降低数值模拟结果对网格的依赖性；同时也验证了壁面函数耦合附面层网格自适应方法，在处理激波诱导引起的附面层流动分离问题时的有效性和准确性。%A finite volume type Reynolds Average Navier-Stokes ( RANS ) solver for separated flows in-duced by shock-boundary layer interaction was presented .Coupling with RANS equations and SST k-ωturbulence model , a turbulent wall boundary condition approach was developed by using wall function model to solve wall shear stress and to modify the viscous flux at the wall boundaries .In addition ,in order to handle the flow separation induced by shock ,a boundary layer mesh adaption technique with the wall function model was employed to refine the boundary layer meshes in the separating area .Numerical stud-ies showed the grid sensitivity decreased by using wall function model .Meanwhile ,the robustness and so-lution accuracy of the present approach in dealing with shock induced flow separation was demonstrated by the numerical results .