高超声速飞行器复杂流场过渡区DSMC数值模拟的一种新方案

A New Version of Hypersonic Vehicle Numerical Simulation in Direct Simulation of Monte Carlo Method of Three Dimensional Flow in Transitional Regime

采用DSMC方法,研究了高超声速三维复杂外形飞行器在过渡领域飞行的气动力、热特性。提出了一种对飞行器物面网格与DSMC计算域网格分别标识,进行高超声速复杂流场过渡区DSMC数值模拟的一种新方案,通过判断模拟分子与表面碰撞来完成飞行器物面网格与DSMC计算域网格间的信息传递和信息存贮,对于复杂外形飞行器的精确描述的物面网格不需做进一步处理,直接应用于不依赖于飞行器外形的DSMC计算的通用子程序中。对物面网格的标识、分子的运动及与表面碰撞的判断、流场量的采集的实施方法和细节进行了分析和讨论。仿真计算了三维复杂飞行器流场压力、热流分布量,飞行器表面气动力、气动力矩和气动热参数,证明了采用的方案和技术的有效性。

In this paper the hypersonic three dimensional flow by the direct simulation of monte carlo method were discussed. A new version of marking respectively the surface position elements and the space cells in hypersonic three dimensional flow by the DSMC method were developed. The transferring and storing of information between the surface position elements and the space cells had been implemented by judging the molecules collision with the surface. In particular, the new problems encountered in describing exactly the surface position element to calculate aerodynamic heating and pressure distribution in the DSMC method had been solved. The overall scheme and the implementation details had been suggested by us. A number of implementation issues had been tackled and discussed ： the marking and Spotting of the surface position elements, the entering of the molecules and the judgment of their colliding with the surface position elements, the special demands raised by the calculation of local fluxes towards the simulation algorithm and the storing of information. The pressure and temperature of the flow field are studied. The analysis of simulation results confirms the validity of the suggested scheme and techniques.