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论文类型：期刊论文
发表时间：2016-01-15
发表刊物：JOURNAL OF COMPUTATIONAL PHYSICS
收录刊物：SCIE
卷号：305
页面范围：677-699
ISSN号：0021-9991
关键字：Acoustic eigenvalue analysis; Boundary element method; Wideband fast multipole method; Contour integral method; Fictitious eigenvalues; Coupling parameter
摘要：An accurate numerical solver is developed in this paper for eigenproblems governed by the Helmholtz equation and formulated through the boundary element method. A contour integral method is used to convert the nonlinear eigenproblem into an ordinary eigenproblem, so that eigenvalues can be extracted accurately by solving a set of standard boundary element systems of equations. In order to accelerate the solution procedure, the parameters affecting the accuracy and efficiency of the method are studied and two contour paths are compared. Moreover, a wideband fast multipole method is implemented with a block IDR(s) solver to reduce the overall solution cost of the boundary element systems of equations with multiple right-hand sides. The Burton-Miller formulation is employed to identify the fictitious eigenfrequencies of the interior acoustic problems with multiply connected domains. The actual effect of the Burton-Miller formulation on tackling the fictitious eigenfrequency problem is investigated and the optimal choice of the coupling parameter as alpha = i/k is confirmed through exterior sphere examples. Furthermore, the numerical eigenvalues obtained by the developed method are compared with the results obtained by the finite element method to show the accuracy and efficiency of the developed method. (C) 2015 Elsevier Inc. All rights reserved.