高超声速流场计算一般采用TVD型格式,这些格式中,大多采用了不同形式的近似黎曼解.通过分析和数值验证,论述了激波捕捉格式中近似黎曼解的耗散性质,说明其对高超声速热流计算的影响.数值实验证明,采用低耗散格式可大大提高热流计算精度,降低热流计算对网格的依赖程度,从而获得精确的热流数值解.
TVD-type schemes are frequently adopted in hypersonic flow simulation. In construction of such kind schemes, approximate Riemann solvers are fundamental. It is investigated through analysis and numerical examination in the present paper that how the dissipative property of approximate Riemann solver affects the aerodynamic heating in numerical simulation of hypersonic flow. Numerical examples show that approximate Riemann solver severely contaminates the boundary layer resolution. If exact Riemann solver adopted, the accuracy of numerical aerodynamic heating could be greatly improved and the grid cell size might be coarser by a factor of 10.