A new concept of modal participation factor for numerical instability in the dual BEM for exterior acoustics |
| |
| Authors: | J T Chen K H Chen I L Chen L W Liu |
| |
| Institution: | a Department of Harbor and River Engineering, National Taiwan Ocean University, P.O. Box 7-59, Keelung 20224, Taiwan;b Department of Naval Architecture, National Kaohsiung Institute of Marine Technology, Kaohsiung 811, Taiwan;c Department of Civil Engineering, National Taiwan University, Taipei 106, Taiwan |
| |
| 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. |
| |
| Keywords: | Modal participation factor Fictitious frequency Exterior acoustics Dual BEM Scattering |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
