核爆炸早中期电磁脉冲产生的数值模拟方法

Numerical simulation method of early-time and intermediate-time electromagnetic pulses generated by nuclear explosions

由于核电磁脉冲(nuclear electromagnetic pulse,NEMP)电场与爆炸当量、爆高、方位角、大气参数和观测位置等密切相关,NEMP产生的数值模拟是非常复杂的问题。本文评述了核爆炸电磁脉冲产生过程的数值模拟方法,包括NEMP产生的物理模型、γ射线和中子在大气中输运及康普顿电流源、大气电导率模型和电磁场求解方法;给出了NEMP的典型数值模拟结果,主要包括早期电磁脉冲和中期电磁脉冲联合模拟结果,并分析了早期电磁脉冲和中期电磁脉冲峰值、起止时间和频谱等特征参数。

As the electric field of the nuclear electromagnetic pulse(NEMP)is closely related to the explosion equivalent,explosion height,azimuth,atmospheric parameters and observation position,the numerical simulation of the nuclear EMP is a very complicated problem.In this paper,the numerical simulation methods of electromagnetic pulse generated in a nuclear explosion are reviewed,including the physical model of NEMP generation,the transport of gamma rays and neutrons in the atmosphere,the Compton current source,the atmospheric conductivity model,and the solution of equations for the electromagnetic field.The typical numerical simulation results of NEMP are given,including the joint simulation results of early-time EMP and intermediate-time EMP,and the characteristic parameters such as peak value,start-stop time and spectrum of early-time EMP and intermediate-time EMP are analyzed.