Papers - Isakari, Hiroshi

弾性体の周波数応答問題に対するトポロジー導関数とレベルセット法に基づくトポロジー最適化

山田崇恭, 飯盛浩司, 松本敏郎, 泉井一浩, 西脇 眞二

日本応用数理学会論文誌 24 ( 2 ) 139-156 2014

Analysis of band structure for 2D acoustic phononic structure by BEM and the block SS method

H. F. Gao, T. Matsumoto, T. Takahashi, H. Isakari

Computer Modeling in Engineering and Sciences 90 ( 4 ) 283-301 2013

Accepted

• Access to Document (DOI)

Investigation of finite/infinite unidirectional elastic phononic plates by BEM

Gao H.F, Matsumoto T, Takahashi T, Isakari H

Enginnering Analysis with Boundary Elements 40   93-103 2013

Accepted

Eigenvalue analysis for acoustic problem in 3D by boundary element method with the block Sakurai-Sugiura method

Haifeng Gao, Toshiro Matsumoto, Toru Takahashi, Hiroshi Isakari

Engineering Analysis with Boundary Elements 37 ( 6 ) 914 - 923 2013

Accepted,  ISSN  0955-7997

　View Summary

This paper presents accurate numerical solutions for nonlinear eigenvalue analysis of three-dimensional acoustic cavities by boundary element method (BEM). To solve the nonlinear eigenvalue problem (NEP) formulated by BEM, we employ a contour integral method, called block Sakurai-Sugiura (SS) method, by which the NEP is converted to a standard linear eigenvalue problem and the dimension of eigenspace is reduced. The block version adopted in present work can also extract eigenvalues whose multiplicity is larger than one, but for the complex connected region which includes a internal closed boundary, the methodology yields fictitious eigenvalues. The application of the technique is demonstrated through the eigenvalue calculation of sphere with unique homogenous boundary conditions, cube with mixed boundary conditions and a complex connected region formed by cubic boundary and spherical boundary, however, the fictitious eigenvalues can be identified by Burton-Miller's method. These numerical results are supported by appropriate convergence study and comparisons with close form. © 2013 Elsevier Ltd.

• Access to Document (DOI)

Calderon's preconditioning for periodic fast multipole method for elastodynamics in 3D

Hiroshi Isakari, Kazuki Niino, Hitoshi Yoshikawa, Naoshi Nishimura

INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING (WILEY-BLACKWELL)  90 ( 4 ) 484 - 505 2012.04

Accepted,  ISSN  0029-5981

　View Summary

Preconditioning methods based on Calderon's formulae for the periodic fast multipole method for elastodynamics in 3D are investigated. Three different types of formulations are proposed. The first type is a preconditioning just by appropriately ordering the coefficient matrix without multiplying preconditioners. The other two types utilise preconditioners constructed using matrices needed in the main fast multipole method algorithms. We make several numerical experiments with proposed preconditioners to confirm the efficiency of these proposed methods. We also conclude that the preconditioning of the first type is faster with respect to the computational time than other preconditioning methods discussed in this article. Copyright (C) 2012 John Wiley & Sons, Ltd.

• Access to Document (DOI)

3次元動弾性学の周期多重極法とその平面2周期構造による散乱問題への適用

飯盛浩司, 吉川仁, 西村直志

応用力学論文集 13   169-178 2010

Accepted

動弾性問題のCIP解析における外挿補間を用いた自由表面の計算

西藤潤, 澤井俊太郎, 飯盛浩司, 田村武

応用力学論文集 13   221-230 2010

Accepted

A periodic FMM for three dimensional elastodynamics with considerations related to Wood's anomaly

飯盛浩司, 大谷佳広, 吉川仁, 西村直志

応用力学論文集 (土木学会)  12   171-178 - 178 2009

Accepted,  ISSN  1345-9139

時間域境界積分方程式法によるレーザ励起弾性波動の指向性に関する数値的検証

飯盛浩司, 吉川仁

応用力学論文集 11   159-166 2008

Accepted