时域有限差分总场吸收边界条件的计算与验证

COMPUTATION AND TEST OF TOTAL-FIELD ABSORBING BOUNDARY CONDITION USING FINITE-DIFFERENCE TIME-DOMAIN METHOD

时域有限差分总场吸收边界条件适用于电磁场总场的计算。与传统散射场的吸收边界条件的表达式不一样 ,此时 ,时域有限差分处理的电磁场是入射场和障碍物散射场的和 ,即总场 ,已经不需要把计算区域分为总场和散射场。入射源直接加在吸收边界上 ,在其上进行边界处理 ,省去连接边界 ,这样逻辑上易于理解 ,编程简单 ,计算速度快。本文推导出总场吸收边界条件公式 ,并用一个三维例子 ,把总场和散射场吸收边界条件的结果进行了对比 。

Absorbing boundary conditions (ABC) of total\|field using finite\|difference time\|domain method can be used in the computational of total\|field of electromagnetic,which is different from traditional ABC because it deals with the sum of incident and scattered waves of electromagnetic field,i.e. total\|field.It doesn't have to divide the computing zone into incident and scattered field. The incident source is applied on the absorbing boundary directly. The connecting boundaries can be omitted. It's easier to understand and program,and faster to calculate.In this paper,the equations of total\|field ABC be induecd.A 3\|dimension example is calculated and the results of tota\|field ABC are compared with those of scatteredzone ABC.