声速再入体表面热流数值模拟研究

本文采用计算效率较高的标量对角化隐式NND格式，通过求解Navier-Stokes方程对影响再入体表面热流计算准确的诸因素进行了综合分析。研究了Steger-Warming通矢量分裂、VanLeer通矢量分裂和通量差分分裂方法及相应熵修正方法对热流的分辨能力，并阐明了在物面边界上采用二阶中心格式、二阶中心和二阶迎风混合格式、以及一阶迎风格式等不同边界格式对热流计算的影响。在此基础上，采用通量差分形式NND格式对钝锥和钝双锥高超声速粘性绕流进行了数值模拟，计算给出了与试验结果相吻合的热流分布。

Numerical study of heat transfer predictionsfor hypersonic reentry bodies

The diagonal form of implicit approximate factorizated NND difference scheme is used to solve the three-dimensional compressible Navier-Stokes equations. A comparative study of the flux vector splitting techniques and the flux difference technique with different entropy fix formula is presented with regards to their ability to accurately predict the heat transfer rate on the surface of blunt body. The effects of grid resolution and boundary schemes on the magnitude of the predicted heat transfer rate are examined. The boundary schemes used are the first-order upwind scheme, the second-order upwind scheme and the central difference scheme. The effects of grid resolution and boundary schemes on the magnitude of the predicted heat transfer rate are illustrated. The hypersonic flows around the blunt cone and the biconic are simulated by using the flux differencing NND scheme. the computational surface heating results are in good agreement with the experimental data.