炸药爆炸过程中电磁辐射数值模拟研究

Numerical simulation of electromagnetic radiation during explosion progress

为了给出炸药爆炸过程中产生电磁辐射的理论分析方法和特性,针对炸药爆炸过程中产生的电磁辐射进行数值模拟研究。采用热平衡电离模型描述爆炸过程中的电离气体,结合爆炸问题的数值模拟方法,得到爆炸场中的电导率分布,进而得到磁扩散率。基于非理想磁流体动力学方程组,计算在特定磁扩散率下的导电气体运动引起的电磁辐射,实现对炸药爆炸产生电磁辐射的数值模拟,数值模拟结果和有关文献符合程度良好。对比不同当量炸药爆炸引起的电磁辐射结果可以得出:炸药爆炸产生的电场信号出现在磁场信号之前;电磁辐射峰值到达的时间随炸药当量增大而增大;磁场信号幅值与当量的2/3次方成正比,电场信号幅值与当量的1/3次方成正比。

The electromagnetic radiation generated explosive explosion has attracted much attention in many fields.In order to give the theoretical analysis method and characteristics of electromagnetic radiation,numerical simulation of electromagnetic radiation was carried out.The thermal equilibrium ionization model was used to describe the ionized gas in the explosion process.Combined with the numerical simulation method of explosion problem,the conductivity distribution and magnetic diffusivity were obtained.Based on the non-ideal magneto-hydrodynamic equations,the electromagnetic radiation caused by the movement of conductive gas under specific magnetic diffusivity was calculated,and the numerical simulation of the electromagnetic radiation was realized.The numerical simulation results are in good agreement with the literature.Comparing the results of electromagnetic radiation produced by different equivalent explosive explosion,it can be concluded that the electric field signal produced explosive explosion appears before the magnetic field signal,and the arrival time of the electromagnetic radiation peak increases with the increase of explosive equivalent.The amplitude of the magnetic field and electric field signal is directly proportional to the 2/3 power and 1/3 power of the equivalent respectively.