Spurious modes in finite-element methods

Author

Sun, Dirt ; Manges, John ; Yuan, Xingchno ; Cendes, Zoltnrz

Author_Institution

Ansoft Corp., Pittsburgh, PA, USA

Volume

37

Issue

5

fYear

1995

fDate

10/1/1995 12:00:00 AM

Firstpage

12

Lastpage

24

Abstract

This paper describes the problem of spurious modes that appear with finite-element solutions of the vector wave equation. It explains that this problem is caused by inconsistent approximations of the static solutions to the wave equation. Tangential-vector finite elements are described that enforce the tangential continuity of the vector field, but leave the normal component discontinuous. It is shown that tangential elements provide consistent approximations of the static solutions to wave problems, and that spurious modes are not produced by this type of finite element. Applications of the theory presented include problems from microwave and antenna design, and from electromagnetic compatibility

Keywords

antennas; electromagnetic compatibility; electromagnetism; finite element analysis; microwave devices; wave equations; antenna design; electromagnetic compatibility; finite-element methods; finite-element solutions; microwave design; spurious modes; static solution approximations; tangential continuity; tangential-vector finite elements; vector field; vector wave equation; wave problems; Eigenvalues and eigenfunctions; Finite element methods; Heart; Null space; Partial differential equations; Permeability; Permittivity; Polynomials;

fLanguage

English

Journal_Title

Antennas and Propagation Magazine, IEEE

Publisher

ieee

ISSN

1045-9243

Type

jour

DOI

10.1109/74.475860

Filename

475860