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On appropriate equivalent monopole sets for rigid body scattering problems
Yves J R Gounot1, Ricardo E Musafir
1Acoustics and Vibration Laboratory, Department of Mechanical Engineering/COPPE/UFRJ, Universidade Federal do Rio de Janeiro, C.P. 68503, Rio de Janeiro, 21941-972, Brazil. ygounot@mecanica.ufrj.br
The Journal of the Acoustical Society of America
|February 6, 2008
Summary
This study identifies optimal monopole arrangements for scattering problems using the equivalent sources method. The "double linear" arrangement proves effective for complex geometries, ensuring accurate solutions with fewer monopoles.
Area of Science:
- Computational electromagnetics
- Numerical methods in physics
Background:
- The equivalent sources method (ESM) is crucial for solving electromagnetic scattering problems.
- Identifying efficient monopole arrangements is key to optimizing ESM for complex geometries.
Purpose of the Study:
- To investigate ESM solution properties for scattering problems.
- To identify optimal monopole arrangements for various scatterer geometries and wave incidence angles.
Main Methods:
- Testing linear, circular, elliptical, and "double linear" monopole supports.
- Analyzing solutions for parallelepiped scatterers with varying aspect ratios.
- Evaluating solution accuracy and monopole count.
Main Results:
- Optimal monopole support configurations depend on scatterer geometry and wave incidence angle.
- The "double linear" support provides satisfactory solutions with minimal monopoles, especially when other supports fail.
- Rules for source number and positioning are derived for different cases.
Conclusions:
- A simple procedure for complex geometries is proposed, ensuring accurate ESM solutions with a low monopole count.
- The findings facilitate efficient numerical simulations in electromagnetic scattering.
- The study offers practical guidelines for applying ESM in antenna and scattering analysis.
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