基于CFD的电磁散射数值模拟

CFD-based numerical simulation of electromagnetic scattering

计算流体力学(CFD)技术中的时域有限体积法(FVTD)被推广到计算电磁学中,直接数值求解时变麦克斯韦方程组。FVTD使用电磁场矢量共置于网格单元中心、散射场积分形式的麦克斯韦方程组守恒形,空间离散使用基于特征值的近似黎曼解构建网格单元边界通量,时间推进采用四阶龙格-库塔法。TM和TE波极化下几种二维完全导电体的表面诱导电流密度和雷达散射截面(RCS)计算验证表明,时域有限体积法是一种高精度有效的时域方法。

The Maxwell equations of electromagnetism which governs electromagnetic phenomena are hypersonic sets of Partial Differential Equations (PDE) as the inviscid Euler equations of aerodynamics, then the Finite-Volume Time-Domain method (FVTD) of Computational Fluid Dynamics (CFD) was extended to Computational Electromagnetics (CEM), and directly numerical computed time dependent Maxwell's equations. A cell-centered, scattered field form Maxwell's equations conservative law was used in FVTD, in which uses characteristic-based approximate Riemann solution to reconstruct spatial flux and four step Runge-Kutta algorithm to time marching. The computed surface inducted current density and radar cross section of several 2-D perfectly conducting scatters in both Transverse-Magnetic (TM) and Transverse-Electric (TE) polarization demonstrated the method was effective and high accurate.