时域瞬变场电磁场有限差分法

A finite-difference time-domain solution for transient electromagnetic fields

模拟电磁场在地下介质中的传播规律是理解地下介质响应的重要手段,直接应用有限差分法在时间域对二维、三维瞬变场进行数值分析是一种有效方法。应用反映电磁场基本规律的麦克斯韦方程组,导出时域场量的齐次扩散方程,对所研究的空间区域作差分离散,源作为初始条件加入,采用合适的边界条件,利用差分方程进行计算,从而得到场量的数值结果,展现瞬变场在地下随时间扩散的全过程,对电磁场的瞬态响应有更加直观的了解。

Simulating electromagnetic fields propagated law in Earth is important medium for understanding the response in Earth. Numeral analysis with finite-difference method in time-domain for two and three dimensional transient field is an effective way. The method derives the homogeneous diffusion equation of time-domain electromagnetic field from Maxwell's equations and does the difference discretion in the investigated region. The source is joined as initial condition and the suitable boundary is adopted,then we can take advantage of the difference equations to get numeral solution of field. Hence it is shown that the entire process of transient electromagnetic field diffusing with time in Earth and it makes better understanding the response of electromagnetic field.