高超声速尖双锥流动高精度数值模拟

以25°/55°尖双锥外形的高超声速低焓层流流动模拟为例,对高阶加权紧致非线性格式模拟激波/边界层干扰流动的能力进行验证和确认。空间离散采用二阶MUSCL和三阶、五阶加权紧致非线性格式,时间离散采用二阶精度双时间步方法,通量函数采用混合Roe-Rusanov,AUSMPW+,Van Leer等,对比了不同精度空间离散格式对时间、网格收敛特性和通量函数耗散特性的影响。数值模拟结果表明采用高精度空间离散格式能在较疏的网格上获得收敛解,并能消除结果对通量函数的敏感性,但收敛需要推进更久的计算时间。数值模拟结果与实验测量结果吻合良好,满足工程精度要求。

Numerical Simulation of Hypersonic Double Cone Flowswith High-order Methods

Hypersonic low enthalpy laminar flows over a 25/55deg double cone geometry were simulated using high-order weighted compact nonlinear schemes (WCNS), and their capabilities to accurately predict laminar shock wave-boundary layer interaction were examined. The simulations were performed with second order MUSCL, third and fifth-order WCNS as spatial discretization schemes. The second-order dual time-stepping approach was employed for time integration. Different flux functions were used for compare, such as hybrid Roe-Rusnov, AUSMPW and Van Leer. We analyzed the effects of high-order methods on time and grid convergence, as well as the dissipation characteristics of flux functions. Finally, we found that high-order methods can get well resolved results on coarse grid, and eliminate the sensitivity of flux functions. However, high-order methods need longer computational time to reach convergence. The computed results show good agreement with experimental data, and the computational accuracy may be characterized as reasonable for most engineering purposes.