过渡领域三维绕流直接统计模拟位置元法的一种新方案

A New Version of Position Element Space Discretization in Direct Statistical Simulation of Three-dimensional Flow in Transitional Regime

本文发展了ＤＳＭＣ方法计算三维绕流位置元方法的新方案，其总体方案和实施细节都是在分析和探索的基础上由我们自己提出的，特别还解决了除气动力、矩总体量以外的气动加热和压力分布等局部分布量的计算所提出的新问题。对于表面位置元的标识、分子的进入及与表面碰撞的判断、网格初始划分与调整、分布量计算对模拟过程及信息存贮所提的特殊要求等进行了分析和讨论，并通过与准确结果的比较证明了采用的方案和技术的有效性。

In the present paper a new version of position element space discretization in calculating three-dimensional flows by the DSMC method is developed. The overall scheme and the implementation details have been suggested by us on the basis of analysis and tests. In particular, the new problems encountered in calculating the various local fluxes such as the acrodynamic heating and pressure distribution besides the overall characteristics such as acrodynamic forces and moments have been solved. A number of implementation issues has been tackled and discussed: the marking and spotting of the surface position elements, the entering of the molecules and the judgement of their colliding with the surface position elements, the initial division and adjustment of the cells,the special demands raised by the calculation of local fluxes towards the simulation argorithm and the storing of information. Comparison with the exact results confirms the validity of the suggested scheme and techniques.