含超強奇異性無網格法於靜電學及電磁波散射問題之應用

The application of hypersingular meshless method for electrostatic and electromagnetic wave scattering problems

李晟煒(Cheng-Wei Lee)

指導教授 ： 楊德良

國立臺灣大學/工學院/土木工程學研究所/碩士(2005年)

https://doi.org/10.6342/NTU.2005.03001

摘要

本論文提出一個含超強奇異性無網格法求解靜電及電磁波散射問題。藉由所提出的去除奇異性技術將含奇異與超強奇異的核函數正規化，本方法因此改善基本解法的缺點，同時將傳統基本解法的無網格的優良的性質被保留下來，而且不用遭遇奇異與數值積分的問題。因為核函數奇異與超奇異性被消除了，源點因此可被放置在真實邊界上且與邊界點重合，具爭議性的虛擬邊界也就可以不用管它了。再則，使用本法並配合領域分割法解決退化邊界的秩不足問題。最後在求解靜電與電磁波散射問題的數值結果例子中與解析解和對偶邊界元素法比較後，證明本法確實可行且精確的。

關鍵字

含超強奇異性無網格法 ； 基本解法 ； 雙層勢能 ； 徑向基底函數 ； 去除奇異性技術 ； 靜電問題 ； 電磁波傳問題 ； 完全導體柱 ； 靜電問題 ； 領域分割法

並列摘要

In this thesis, a hypersingular meshless method (HMM) is proposed to solve electrostatic and electromagnetic wave scattering problems. This method modifies the method of fundamental solutions (MFS) by using the desingularized technique to regularize the singularity and hypersingularity of the proposed kernel functions. In the meantime the meshless features of conventional MFS are preserved without singularity and numerical integration. The source points can be located on the real boundary coincident with boundary points since the diagonal terms of influence matrices are determined after the singularity and hypersingularity having being eliminated. So that testing to the controversial off-boundary distance can be avoided. Furthermore, by using the HMM in conjunction with domain decomposition technique, we also solve for the rank-deficiency problem with degenerate boundary. The numerical results are demonstrated it valid and accuracy in solving a number of testing cases for electrostatic and electromagnetic wave scattering problems after comparing with exact solutions and the results made by dual boundary element method.

並列關鍵字

Hypersingular meshless method ； method of fundamental solutions ； double layer potential ； radial basis function ； desingularized technique ； electrostatic problem ； electromagnetic wave scattering problem ； perfectly conducting cylinder ； multi-domain technique

參考文獻

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