Current Computation by the Finite Element Method.

Abstract

The problem concerning scattering of a plane electromagnetic wave from a thin conducting square plate is easy to formulate but very difficult to solve. The major difficulties are due to (1) the edge condition, (2) the highly if not nonintegrable singularity of the dyadic Green's function associated with a two-dimensional surface, and (3) the stability problem caused by its thinness. Obviously, attempts to seek a closed form solution are bound to fail, and the only promising approach is to use numerical methods. Although the moment method has been demonstrated in many cases to be a very successful numerical method for electromagnetic problems, its application to a two-dimensional problem has not been good. The MOM offers two approaches to solve the surface current problems. One is the wire grid modeling which suffers from many numerical and physical difficulties. The geometrical structure is modeled into a wire grid representation and the results are sensitive to selected wire radius. Grid representation of the structure has loops and thus loop currents can be excited which are manifestly unphysical. Again, depending on the grid structure, internal resonance may occur and thus, alter the external resonances. The other approach is the surface patch modeling. Here the results seem to vary drastically with slight changes in patch size.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Nov 01, 1976
Accession Number
ADA035223

Entities

People

  • A. Sankar
  • T. C. Tong

Tags

Communities of Interest

  • Air Platforms
  • C4I

DTIC Thesaurus Topics

  • Boundary Value Problems
  • Computer Programs
  • Computers
  • Coordinate Systems
  • Current Density
  • Electromagnetic Scattering
  • Electronics Laboratories
  • Equations
  • Finite Element Analysis
  • Geometry
  • Grids
  • Integral Equations
  • Mechanics
  • Numerical Integration
  • Quadrants
  • Scattering
  • Two Dimensional

Readers

  • Applied Combinatorial Optimization and Logic Circuit Design.
  • Electromagnetic Wave Scattering and Antenna Radiation Engineering
  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)