直接驱动柱内爆流体力学不稳定性数值模拟

Numerical simulation of hydrodynamic instability in direct-drive cylindrical implosion

给出了LARED S程序对直接驱动柱内爆流体力学不稳定性模拟的物理方程,介绍了一种直接驱动柱内爆靶的结构,给出了模拟中使用活动网格追踪和其他一些需要注意的问题。对OMEGA激光器直接驱动柱内爆实验物理模型进行了简化处理:使用理想气体状态方程,假设烧蚀层、标识层和内部填充材料为同一介质,只在密度上有差别;采用全电离和单温近似,在内爆过程中仅考虑热传导过程而忽略辐射和非局域电子热传导等过程的影响。模拟结果表明:LARED S程序与LASNEX程序的计算结果基本上符合。

The physical equations of direct-drive cylindrical hydrodynamic instability in the LARED-S code, the geometry for the direct-drive cylindrical targets, the slide grids and some related techniques in the simulation are given.. In the simulation of direct-drive cylindrical implosion experiments at OMEGA laser facility, the physical model of the target is simplified. The ablator, the marker layer and the interior foam of the target are taken as ideal gases, with different densities and the completely ionized charge state and single-temperature approximation are supposed during the implosion. The effect of classical electron thermal conduction is included while other factors such as radiation transport and nonlocal electron transport are neglected in the calculations. Simulation results of the LARED-S code show agreement with those of the LASNEX code on the whole.