等离子体散射分析的改进型交替隐式时域方法

An improved ADI-FDTD method for computing the scattering properties of unmagnetized plasma

提出了一种改进的交替隐式时域有限差分(FDTD)方法,运用该方法分析了等离子体涂覆导体圆柱的散射特性,为等离子体隐身技术的运用提供了一定的理论指导.该方法在整个问题空间采用完整场形式的场量进行迭代计算,并运用中心差分格式离散极化电流密度辅助方程.仿真实验表明:提出的算法具有无条件稳定特性,其计算效率明显优于以往文献提出的交替隐式FDTD方法,在精度和效率上也稍高于普通的显式FDTD方法.

An improved alternative direction implicit-finite difference time domain （ADI-FDTD） method to simulate the electromagnetic characteristics of the nonmagnetized plasma is presented. The scattering characteristics of a perfectly conducting cylinder coated by a layer of unmagnetized plasma are investigated by this method, which provides a certain theoretical guidance to plasma stealth technology. By bringing the central difference operator into the discrete treatment of auxiliary equations and using the complete electromagnetic （EM） fields in the FDTD iteration in the full electromagnetic problem space, this method avoids the time-consuming calculations and obtains the unconditionally stability. Numerical experiments show that this method not only improves accuracy and efficiency over the conventional explicit FDTD methods, but also spends much less computational time than the ADIFDTD method proposed in the recent reference based on the same accuracy.