在自适应重叠网格系统下,数值求解非定常Navier-Stokes方程,开展了钝前缘三角翼跨声速流场的计算研究.目的在于考察交叠网格系统下,不同迎角的跨声速来流条件时流场细节的捕捉能力.其中,网格方面采用了贴体网格块精确描述机体外形,采用与之交叠的可自适应的直角网格捕捉脱体涡系的发展变化及涡与激波的干扰;求解涡黏性计算方面,采用了Spalart-Allmaras(SA)及其对应的Detached Eddy Simulation(DES)模型.基于以上描述的方法,针对钝前缘三角翼在来流马赫数0.85不同迎角状态进行了计算,比较了雷诺平均与DES计算的结果差异.计算结果表明,在重叠网格系统下,网格构建简便,适用性好,计算具备一定的数值精度;对于大迎角状态,DES方法能够有效地模拟脱体涡系的发展变化,获得更好的计算结果.%Based on adaptive overlapped grid system,a transonic flow around delta wing with blunt leading edge was simulated by solving the Navier-Stokes equations.The ability of this grid system in capturing the flow field details was observed at different angles of attack and transonic inflow conditions.A body-fitted grid block was used to accurately describe the delta wing configuration,and an adaptive overlapped grid was adopted for the vortex evolution and the shock/vortex interaction.The Spalart-Allmaras (SA)turbulence model and the corresponding Detached Eddy Simulation (DES)method were used for the eddy viscosity estimation.The SA model results were compared with those of the DES at different angles of attack and Mach 0.85. Better results were obtained by the DES method with high angle of attack due to its capability of capturing massive separations.The grid generation in this system is relatively inexpensive,and the simulation results based on this grid system are numerically accurate.The present methods are suitable for delta wing shock/vortex interaction simulation.
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