一种强鲁棒性的时域非连续伽略金可穿透薄层算法  

A robust discontinuous Galerkin time domain algorithm for penetrable thin layers

作　　者：杨谦[1] 魏兵[1] 李林茜[1] 邓浩川 Yang Qian;Wei Bing;Li Lin-Qian;Deng Hao-Chuan(School of Physics,Xidian University,Xi’an 710071,China;The Science and Technology on Electromagnetic Scattering Laboratory,Beijing 110000,China)

机构地区：[1]西安电子科技大学物理学院,西安710071 [2]电磁散射重点实验室,北京110000

出　　处：《物理学报》2023年第8期67-76,共10页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:61901324,62001345);中国博士后科学基金(批准号:2019M653548,2019M663928XB);电波环境特性及模化技术国防科技重点实验室基金(批准号:201903002);电磁散射重点实验室基金(批准号:61424090111);中央高校基本科研业务费(批准号:XJS200501,XJS200507,JB200501)资助的课题.

摘　　要：本文研究了时域非连续伽略金算法(discontinuous Galerkin time-domain,DGTD)中的可穿透薄层问题,薄层问题属于多尺度问题,精确建模资源消耗太高难以实施,可采用近似方案.研究发现采用等效表面电流激励易产生发散,为提高计算方案鲁棒性,研究了电磁场修正方案,这一方案允许采用参数很大的薄层(高介电系数),其计算方法简便易行.此外,还给出了多层介质薄层的仿真方案,并对相关数值算例进行验证,结果说明了本文算法的精确性和有效性,本文方案可用于复杂薄层电磁问题的快速求解.The thin layer problem is common in some engineering cases,such as a coating target or dielectric radome.If the skin depth of the medium behind the thin layer is much smaller than the medium scale,the transmission line impedance boundary can be used to solve the thin layer problem.When both sides of the thin layer are free space or the skin depth of the medium behind the thin layer is greater than or comparable to the scale of the medium,the transmission line impedance boundary condition is not applicable.Such problems need incident and reflected wave data and are also known as penetrable thin-layer problems.When dealing with penetrable thin-layer problems,we need to give the electromagnetic wave data on both sides.In addition,the thin layer problem can belong with multi-scale problems.The EM simulation is difficult to implement because of the high resource consumption of accurate modeling.The accurate modeling is a very expensive algorithm,and the mesh-size difference between the thin layer region and the surrounding ordinary region is too large,thus seriously affecting the quality of the elements(tetrahedrons).So,it is difficult to solve the problem of thin layer quickly by using the time-domain discontinuous Galerkin method or even by using local time steps or other optimization methods.To acquire a fast solution,the approximate boundary condition can be used to describe the thin layer.The DGTD has also the advantage of the geometric fitting property.If a thin layer model is curved,we can build a conformal geometric model to deal with the thin layer,thus avoiding the complicated interpolation correction scheme.In this work,A robust DGTD method for penetrable thin layers is proposed.In our study,we find that the current excitation scheme is prone to divergence when large dielectric coefficients are dealt with and its robustness is poor.To solve this problem,we use the electromagnetic field correction scheme in DGTD to deal with the thin layer problems.In addition,engineering problems may encounter multiple thin

关 键 词：可穿透薄层 多尺度问题 时域非连续伽略金算法 

分 类 号：TP18[自动化与计算机技术—控制理论与控制工程] O441.4[自动化与计算机技术—控制科学与工程]