Hidehito Iwase

Parallel implementation of boundary element method with domain decomposition

Algorithms for the parallel boundary element computation of the domain-decomposed problem are considered in this paper. In this method, boundary conditions on virtual internal boundaries are assumed, and then the boundary element analysis for each subdomain is performed in parallel. The assumed conditions are modified according to the numerical results and the process returns to parallel computation. The Uzawa and the Schwarz methods without domain overlap are applied as alternative schemes on the internal boundary. The methods are implemented on the cluster computing system in order to examine the schemes from the view-point of the convergency of the solution.

Parallel computing for the combination method of BEM and FEM

A new algorithm for the parallel computing of the boundary-element and finite-element combination method is presented in this paper. By introducing the domain decomposition of an entire domain under consideration into the boundary-element and finite-element subdomains, each analysis is performed independently and in parallel. A renewal iterative scheme for parallel computing is the Schwarz method which was previously adopted to the domain decomposition parallel scheme in boundary-element analysis. A cluster parallel computing system by workstations connected by the LAN is constructed and employed aiming at efficient analysis. Convergence and accuracy of solutions on the internal virtual boundaries are shown through some sample examples.

BEM and FEM combination parallel analysis using conjugate gradient and condensation

Abstract Boundary element and finite element combination analysis on parallel schemes are improved in this paper. The conjugate gradient method (CG method) is introduced for renewal of unknowns on the combination boundary in place of the Schwarz method previously used, which makes it possible to determine a parameter required in the renewal iteration automatically. Further, the condense method is employed for higher efficiency of solution by reducing the number of degree of freedoms in both equations for the finite element and boundary element domains. Comparison of the present algorithm with the previous one in some numerical examples shows marked improvement in computational efficiency.

Performance evaluation of parallel boundary element analysis by domain decomposition method

The authors previously applied an iterative scheme of domain decomposition algorithms for parallel computing to boundary element analysis in potential problems. The purpose of this paper is comparison and evaluation of the efficiency of the scheme using a network cluster system of workstations, for different conditions of number of boundary elements and load balance/unbalance in each domain. Utility is shown through some example computations including a mold IC electronic device.

Parallel adaptive boundary element analysis

Abstract This paper presents parallel implementation of the adaptive boundary element method based on the error analysis called ‘sample point error analysis and releated mesh refinement by extended error indicator’ proposed previously by the authors. Cluster computing on workstations connected by local area network is performed. Decomposition of the adaptive scheme process into two parts is introduced; one is ordinary boundary element analysis and the other the sample point error analysis, and these parts are carried out in parallel with different workstations. Results proved usefulness of the proposed parallel scheme.