Mesh truncation conditions for finite element/finite difference simulations of electromagnetic wave phenomena in unbounded regions.

Persistent Link:
http://hdl.handle.net/10150/186069
Title:
Mesh truncation conditions for finite element/finite difference simulations of electromagnetic wave phenomena in unbounded regions.
Author:
Wright, Diana Beth.
Issue Date:
1992
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
A new local method for finite difference/finite element mesh truncation in the frequency domain is investigated. The method is based on the Measured Equation of Invariance (MEI) concept recently proposed by Mei, et al. (1) for the numerical solution of electro-magnetic wave scattering by perfectly conducting targets in unbounded regions. An MEI is a numerically derived discrete, linear equation which relates the field at a given boundary node to the field values at neighboring nodes. For each boundary node, a different MEI is constructed. Given such a condition for each node, a computationally efficient and accurate FD/FE grid truncation can be achieved. Since the derivation of the MEI is not based on any far-field assumptions, unlike most other local methods, the mesh truncation condition can be applied just a few cells away from the scatterer's boundary. The method is extended to treat the case of penetrable scatterers. Three different approaches are considered. The first is based upon a direct application of Huygen's principle. The second relies on equivalent source concepts. The final method proposed employs a distribution of multipoles, referred to as multiple multipoles, to generate the MEI's. The MEI-based mesh truncation conditions are implemented for the first time in a finite element formulation and numerical results are presented for time-harmonic scattering by a variety of two-dimensional targets. The feasibility of constructing an accurate truncation condition for the mesh interior to a homogeneous penetrable scatterer is also examined. In addition to the study conducted for finite difference/finite element mesh truncation in the frequency domain, a time domain truncation scheme based on the principles of linearity and superposition is considered. The method is demonstrated for a guided wave structure.
Type:
text; Dissertation-Reproduction (electronic)
Keywords:
Dissertations, Academic.; Electrical engineering.
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Electrical and Computer Engineering; Graduate College
Degree Grantor:
University of Arizona
Committee Chair:
Cangellaris, Andreas

Full metadata record

DC FieldValue Language
dc.language.isoenen_US
dc.titleMesh truncation conditions for finite element/finite difference simulations of electromagnetic wave phenomena in unbounded regions.en_US
dc.creatorWright, Diana Beth.en_US
dc.contributor.authorWright, Diana Beth.en_US
dc.date.issued1992en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractA new local method for finite difference/finite element mesh truncation in the frequency domain is investigated. The method is based on the Measured Equation of Invariance (MEI) concept recently proposed by Mei, et al. (1) for the numerical solution of electro-magnetic wave scattering by perfectly conducting targets in unbounded regions. An MEI is a numerically derived discrete, linear equation which relates the field at a given boundary node to the field values at neighboring nodes. For each boundary node, a different MEI is constructed. Given such a condition for each node, a computationally efficient and accurate FD/FE grid truncation can be achieved. Since the derivation of the MEI is not based on any far-field assumptions, unlike most other local methods, the mesh truncation condition can be applied just a few cells away from the scatterer's boundary. The method is extended to treat the case of penetrable scatterers. Three different approaches are considered. The first is based upon a direct application of Huygen's principle. The second relies on equivalent source concepts. The final method proposed employs a distribution of multipoles, referred to as multiple multipoles, to generate the MEI's. The MEI-based mesh truncation conditions are implemented for the first time in a finite element formulation and numerical results are presented for time-harmonic scattering by a variety of two-dimensional targets. The feasibility of constructing an accurate truncation condition for the mesh interior to a homogeneous penetrable scatterer is also examined. In addition to the study conducted for finite difference/finite element mesh truncation in the frequency domain, a time domain truncation scheme based on the principles of linearity and superposition is considered. The method is demonstrated for a guided wave structure.en_US
dc.typetexten_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.subjectDissertations, Academic.en_US
dc.subjectElectrical engineering.en_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineElectrical and Computer Engineeringen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.chairCangellaris, Andreasen_US
dc.contributor.committeememberDudley, Donalden_US
dc.contributor.committeememberDvorak, Stevenen_US
dc.contributor.committeememberChow, Kwoken_US
dc.identifier.proquest9309030en_US
dc.identifier.oclc714159988en_US
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