A Novel Conversion Technique from Nodal to Edge Finite Element Data Structure for Electromagnetic Analysis

Durgarao Kamireddy; Arup Nandy

doi:10.24423/cames.384

Durgarao Kamireddy Indian Institute of Technology Guwahati
Arup Nandy Indian Institute of Technology Guwahati

DOI: http://dx.doi.org/10.24423/cames.384

Abstract

Standard nodal finite elements in the electromagnetic analysis have a well-known limitation of the occurrence of a spurious solution. In order to circumvent the problem, a penalty function method or a regularization method is used with the potential formulation. These methods solve the problem partially by pushing the spurious mode to the higher end of the spectrum. But it fails to capture singular eigenvalues in the case of the problem domains with sharp edges and corners. To circumvent this limitation, edge elements have been developed for the electromagnetic analysis where degree of freedom is along the edges. But most of the preprocessors develop complex meshes in the nodal framework. In this work, we have developed a novel technique to convert nodal data structure to edge data structure for electromagnetic analysis. We have explained the conversion algorithm in details, mentioning associated complexities with relevant examples. The performance of the developed algorithm has been demonstrated extensively with several examples.

Keywords

FEM, Electromagnetics, Edge finite elements, Eigenvalue analysis,

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