强爆炸火球数值模拟中的算子分裂方法  

An Operator Splitting Method for Numerical Simulation of Strong Explosion Fireball

作　　者：闫凯[1] 李若[2] 田宙[1] 郭永辉[1] 曹渊[1,3] 

机构地区：[1]西北核技术研究所,西安710024 [2]北京大学数学系,北京100871 [3]长安大学,西安710054

出　　处：《计算物理》2013年第3期379-386,共8页Chinese Journal of Computational Physics

摘　　要：采用算子分裂方法将辐射流体力学方程组分裂为对流项和刚性源项,设计一种高效求解刚性源项方程组的数值方法.数值实验表明:该方法对时间步长不敏感,计算精度能够满足工程计算要求.在不对方程组做任何近似的情况下,数值给出了较长时间内火球冲击波阵面压力峰值及阵面位置的变化,结果与实际强爆炸中的经验公式吻合较好.An operator splitting method is developed for numerical simulation of strong explosion fireball.In the approach the system is split into two parts.One part couples radiation and fluid in a hyperbolic subsystem.Another parabolic part evolves radiation diffusion and source-sink terms.We propose a numerical method for stiff source term.It shows that the method maintains efficiency and satisfies the needs of engineering.At last,spatial distributions of parameters in nuclear explosion reflecting fireball evolution are given.The calculation agrees well with empirical formulas.

关 键 词：火球 辐射流体力学 刚性源项 算子分裂方法 

分 类 号：O38[理学—流体力学] O242[理学—力学]