| The technology of parallel computation is introduced into the structure Boundary Element(BE) analysis to multiply the size of problem to solve, accelerate the analysis and facilitate the large-scale application and real-time application in the locale. Under the networked PC cluster parallel computing environment, the parallel Boundary Element Method(BEM) used to analyze elasto-static, elasto-dynamic and elasto-plastic structure is studied in this dissertation and applied to analysis of hydraulic structure. The main contents of this dissertation are as follows:(1) A new networked PC cluster parallel computing environment is set up,which is simple and easy to use. The detailed method of configuration and use is presented.(2) The concept of BEM equations node-super-row is presented. The node-super-row wrap distributed storage scheme is used to implement the BEM equations parallel formation and load balance. Based on this distributed storage, the in-core parallel Gauss-Jordan eliminating method of single domain BE equations is improved. An out-of-core algorithm to solve single domain BE equations is developed by interacting between in- and out-of-core. Based on the size of core and number of working space, the data is blocked. The parallel Gauss-Jordan eliminating method is used in the same block and the wrap cyclic modification method is presented for elimination between the different blocks. A local in-block pivoting technique is used in out-of-core algorithm to balance external memory access, communication, numerical stability and numerical accuracy. In the parallel program, the in-core and out-of-core algorithms can be identified and chosen to use automatically. So the algorithms are united.(3) The re-orthonormalization technique is used to solve the loss of orthonormality of basis vector during the classical GMRES method solving large-scale three dimensional elasto-static BE problems. Based on the characteristic of fundamental solution and the coefficient matrix, several precondition methods are studied. By using the technique of re-orthonoramalization and precondition, the practical GMRES method is developed based on the classical one. The complexity and parallelism of the classical GMRES are analyzed. The idea of combining the practical technique with parallel technique is presented and the parallelization of practical GMRES is implemented. The corresponding serial and parallel programs are developed and different numerical tests are carried out.(4) A BE sub-region parallel algorithm is presented. This algorithm can identify and choose in-core or out-of core algorithm based on different scale of computation and cluster during each computing phase. And parallelization during each phase is implemented. This algorithm can solve the residual equations parallelly and the current data distribution of residual equations does not change.(5) Two load-balance sub-region parallel algorithms with different parallel granularity are presented to solve different combination of sub-region partition and cluster configuration. They are multi-domain-one-processor algorithm and multi-processor-one-sub-region algorithm. These algorithms all allocate tasks uniformly based on the evaluation of computational load and the parameters of cluster. The difference between these two algorithms is that the former uses sub-domainas the basic unit of task to be allocated and the latter uses the node-super-row as the basic unit of task.(6) The original problem is transformed into transformed domain by using Laplace transform method. By the parallelization of the BEM in the transformed domain, the parallelization of the elasto-dynamic BE analysis is implemented By introducing the time related fimdamental solution, the time dependency is released from the formation of time-domain BE equations. The time stepping method is parallelized by distributed parallelization of the matrical computing. The parallel time-domain BEM is a partial time-parallel algorithm.(7) The computational complexity and parallelism of t...
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