关键词: 超声速冲击射流;紧致格式;大涡模拟;涡合并;激波涡干扰

Abstract: To study the details of flow structure of moderately under-expanded supersonic impinging jet,numerical simulation was conducted with large-eddy simulation.A third-order upwind compact difference and a fourth-order symmetric compact scheme were employed to discretize the nondimensional axisymmetric compressible Favre-filtered Navier-Stokes equations in space,while the third-order Runge-Kutta method with property of TVD was adopted to deal with the temporal discretization.The sub-grid scale model was formulated according to the modified Smagorinsky Eddy-viscosity model.The code was demonstrated by experimental data.The numerical simulation successfully captured the shock wave structure in the jet plume and vortex structure with different scales in the shear layer and in the wall jet.The result shows that vortex merging occurs more frequently upstream in the shear layer than that does downstream.The interaction between plate shock wave and vortex makes intensity and location of the shock wave vary greatly.It also causes the significant change of the pressure of impinging zone on the plate and vortex distortion.

Key words: Supersonic impinging jet;Compact scheme;Large-eddy simulation;Vortex merging;Shock-vortex interaction