分布式负载垂直极化有界波电磁脉冲模拟器外泄场的规律分析

Regularity analysis of leakage-field from vertically polarized bounded wave electromagnetic pulse simulator with distributed load

将基于MPI平台的并行时域有限差分(FDTD)方法与基于完全磁导体(PMC)镜像法相结合,并结合CST模拟软件,模拟给出分布式负载垂直极化有界波电磁脉冲(EMP)的外泄场(包括侧泄场和后泄场)的分布规律。模拟结果与实验结果符合得很好。研究表明:在高度方向上,地面附近的外泄场峰值最大,但远离模拟器时,在1.5 m高的高度范围内,外泄场的峰值差别不大;不管采用何种双指数脉冲源,距离模拟器边缘位置比较近的测点在传输线段的侧泄场的幅值大于分布式负载段侧泄场的幅值,且两者都大于分布式负载末端的后泄场幅值,但随着测点与模拟器边缘的垂直距离的增加,分布式负载段的后泄场可能会比侧泄场大;对于电压峰值相同的双指数激励源而言,所含的高频分量越多,在一定范围内,从其分布式负载末端外泄的后泄场更大;模拟器下方大地的电导率增加,模拟器的外泄场增加。

A parallel finite difference time domain(FDTD)method combined with perfectly magnetic conductor(PMC)image method and CST software is firstly presented for computing the leakage field(including sideward and backward leakage field)from vertically polarized bounded wave electromagnetic pulse(EMP)simulator with distributed load.The results got from simulation agree well with those from experiment.Numerical results show that the leakage field’s peak-value near the ground reaches maximum in the direction of height,but there’s little difference of leakage fields’peak-values at the testing points under 1.5 m height and far away from the simulator;The peak-values of sideward leakage field from simulator’s transitional section are larger than those from distributed load section,both of them are larger than the backward leakage field from the end of distributed load section,as the testing point is near the simulator,and the backward leakage field may be larger than those sideward leakage fields,as the vertically distance between the testing point and the simulator increases;The regularity conclusion suits for the simulator with different double exponential source.The more excited source component in high frequency domain,the larger backward leakage field in some distance domain.The leakage field from the simulator increases,as ground’s conductivity increases.