合元极技术再认识——一种电大复杂目标散射混合计算技术的考察

Further Cognition of Hybrid FE/BI/MLFMA——Investigation of the Hybrid Computing Technique for Scattering by Large Complex Targets

合元极技术,即混合有限元、边界元、快速多极子技术,是计算电磁学中近年来日益受到关注的一种精确、高效、通用的技术.本文首先将此技术推广应用于既带涂层又带腔的复杂电大目标电磁散射的计算;接着对合元极技术各种算法的计算精度、迭代收敛速度进行了理论和数值实验的分析研究;然后,从通用性和高效性的角度,对作者采用的不对称合元极技术和近来来其他作者提出的对称合元极技术做了分析比较.最后,本文计算了几种复杂目标的散射截面以证实此项技术的高效、通用.

A general hybrid finite-element/boundary-integral/multilevel fast multipole algorithm （FE/BI/MLFMA） is presented for computation of scattering by large complex targets. Various algorithms of the hybrid FE/BI/MLFMA are presented and compared heuristically and numerically in this paper. The accuracy and iterative convergence speed of these algorithms are investigated in detail. Furthermore ,the presented asymmetric formulation of the hybrid FE/BI/MLFMA in this paper is compared, from the point of the generality and efficiency views, with the symmetric FE/BI/MLFMA formulation recently proposed by other authors. A general, accurate, and efficient code based on an efficient algorithm of the hybrid FE/BI/MLFMA is developed for large complex targets. The scattering by several large complex targets is computed at last in this paper.