A new concept of modal participation factor for numerical instability in the dual BEM for exterior acoustics
Journal
Mechanics Research Communications
Journal Volume
30
Journal Issue
2
Pages
161-174
Date Issued
2003
Author(s)
Abstract
This paper presents the occurring mechanism why irregular frequencies are imbedded in the exterior acoustics using the dual boundary element method (BEM). The modal participation factor which dominates the numerical instability is derived for continuous and discrete systems. In addition, the irregular (fictitious) frequencies embedded in the singular or hypersingular integral equations are discussed, respectively. It is found that the irregular values depend on the kernels in the integral representation for the solution. A two-dimensional dual BEM program for the exterior acoustics was developed. Numerical experiments are conducted to verify the concept of modal participation factor. © 2002 Elsevier Science Ltd. All rights reserved.
Subjects
Dual BEM; Exterior acoustics; Fictitious frequency; Modal participation factor; Scattering
Other Subjects
Boundary element method; Frequencies; Integral equations; Modal analysis; Numerical methods; Exterior acoustics; Acoustics
Type
journal article