过渡区DSMC数值模拟的一种自适应当地时间步长新方法  

An Adaptive Local Time Step New Approach for the Direct Simulation of Monte Carlo Method in the Transitional Regime

作　　者：朱荣丽[1] 

机构地区：[1]北京航天长征飞行器研究所,北京100076

出　　处：《宇航学报》2008年第4期1142-1146,1156,共6页Journal of Astronautics

摘　　要：采用优化的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。对建立在流场网格和物面网格耦合基础上的三维复杂流场DSMC通用程序进行了变时间步长的优化设计,发展了一种自适应当地时间步长新方法,根据网格内仿真分子的碰撞数,自动调整网格中进行仿真分子运动和碰撞计算的时间步长,有效地提高了程序的计算效率。对比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、热分布参数,证明了自适应当地时间步长新方法大幅度缩短了流场稳定所需的CPU时间,并且不降低流场模拟结果的精度。In this paper the hypersonic three dimensional flows by the direct simulation of monte carlo method were discussed. An adaptive local time step new approach was applied to this general code in order to make the code more efficient. The automatic adaptation of this time step allowed an appropriate resolution of the local collision frequency a control of the collision probabilities. The comparison between the code with and that without adaptive local time stem new method showed that this method resulted in a significant reduction in the execution CPU time, but has no influence on the simulation resolution and the flow structure.

关 键 词：DSMC数值模拟 三维流场 网格标识 分子碰撞 

分 类 号：V211.3[航空宇航科学与技术—航空宇航推进理论与工程]