一种DSMC分子仿真下的权因子预定义方法  

A New Predefined Method of Particle Weight in DSMC Molecular Simulation

作　　者：黄飞[1] 沈清[1] 程晓丽[1] 赵波[1] 

机构地区：[1]中国航天空气动力技术研究院,北京100074

出　　处：《航空学报》2014年第8期2174-2181,共8页Acta Aeronautica et Astronautica Sinica

摘　　要：为提高直接模拟蒙特卡罗(DSMC)方法的计算效率,针对模拟初始DSMC方法中权因子难以确定的问题,通过分析权因子在DSMC方法模拟中的定义及求解方法,提出了一种DSMC分子仿真下权因子的预定义求解方法,采用平板、钝锥等典型算例验证了该方法的正确性。结果表明:权因子预定义方法能够在模拟初始提前对权因子的分布特征进行预定义求解;该方法能够使得DSMC仿真时全场的仿真分子数分布更为合理,在保证计算精度的前提下减少全场的仿真分子数,节省内存,提高计算效率。For improving computation efficiency of the direct simulation Monte Carlo （DSMC） method and overcoming the difficulty of prior knowledge about particle weight before the starting of DSMC simulation,a new predefined solution method of the particle weight is introduced,which can be obtained by analyzing its definition and solution method in DSMC.Validity about this method is investigated by analyzing both flat plate and blunt cone flow fields.The results show that present method can solve the particle weight distribution characteristics before the starting of simulation.The number of simulated particles is distributed more uniformly in the whole flow field with this method when comparing it with the constant particle weight.The number of simulated molecules can also be reduced effectively without causing any accuracy loss.The method also can save internal storage and improve computation efficiency.

关 键 词：DSMC 非结构网格 权因子 稀薄气体 计算效率 

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]