超高速碰撞电磁效应数值模拟

采用理论分析和数值模拟结合的方法对超高速碰撞产生等离子体问题进行研究. 通过SPH方法,建立二维轴对称模型,针对不同碰撞速度进行数值模拟,对比不同时刻碎片云的形状以及膨胀速度,验证数值模拟的正确性;利用Thomas-Fermi模型,计算超高速碰撞过程中SPH粒子的温度,对于发生汽化的部分考虑其产生的等离子体参数;以统计物理学为基础,基于化学反应动力学原理,建立了非热平衡等离子体电子数密度、电子温度、宏观温度以及内能之间的关系,用以计算超高速碰撞过程中产生等离子体的参数. 给出不同时刻碰撞产生的总电荷数随时间的变化,将数值模拟结果与文献中经验公式结果进行对比,验证了本文中计算超高速碰撞产生等离子体方法的正确性.

Numerical Simulation of Hypervelocity-Induced Electromagnetic Effect

Hypervelocity impact generated plasma (HVIGP) was investigated through both theoretical analysis and numerical simulation. The 2-D axially symmetric model was established based on the smoothed particle hydrodynamic method, to numerically simulate the impacts of different velocities and verified by comparing to the debris clouds and expansion velocity. The SPH particle temperatures at different hypervelocity were calculated by the Thomas-Fermi model and considering the plasma parameters as the vaporized parts. In addition, the relationships between the electron density of the thermal non-equilibrium plasma, the electron temperature, the macro-temperature, and the internal energy were given based on statistical physics and chemical reaction dynamics to calculate the parameters of HVIGP. Total charges of HVIGP at different times were simulated. The simulated results are compared with the calculated results by the empirical formula, indicating that the method used to calculate HVIGP in this paper is correct.