A mathematical program is proposed for the highly nonlinear problem involving frictional contact. A program-pattern using the fast multipole boundary element method (FM- BEM) is given for 3-D elastic contact with fric...A mathematical program is proposed for the highly nonlinear problem involving frictional contact. A program-pattern using the fast multipole boundary element method (FM- BEM) is given for 3-D elastic contact with friction to replace the Monte Carlo method. A new optimized generalized minimal residual (GMRES) algorithm is presented. Numerical examples demonstrate the validity of the program-pattern optimization model for node-to-surface contact with friction. The GMRES algorithm greatly improves the computational efciency.展开更多
Small disturbance potential theory is widely used in solving aerodynamic problems with low Mach numbers,and it plays an important role in engineering design.Concerning structure wind engineering,the body of the struct...Small disturbance potential theory is widely used in solving aerodynamic problems with low Mach numbers,and it plays an important role in engineering design.Concerning structure wind engineering,the body of the structure is in a low velocity wind field,with a low viscosity of air and thin boundary layer,therefore,the tiny shear stress caused by the boundary layer can be ignored,only wind pressure being considered.In this paper,based on small disturbance potential theory,the fluid-structure interaction between the wind and membrane structure is analyzed by joint utilization of the boundary element method(BEM)and finite element method(FEM)through a loose-coupling procedure.However,the boundary of flow field to be calculated is not fully smooth,corners and edges still exist,so the discontinuous boundary element is introduced.Furthermore,because a large scale boundary element equation set with a nonsymmetrical coefficient matrix must be solved,this paper imports a preconditioning GMRES(the generalized minimum residual)iterative algorithm,which takes full advantage of the boundary element method.Several calculation examples have verified the correctness and soundness of the treatments mentioned above.展开更多
This paper presents a new mathematical model for the highly nonlinear problem of frictional con- tact. A programming model, multipole boundary element method (BEM), was developed for 3-D elastic con- tact with frict...This paper presents a new mathematical model for the highly nonlinear problem of frictional con- tact. A programming model, multipole boundary element method (BEM), was developed for 3-D elastic con- tact with friction to replace the Monte Carlo method. A numerical example shows that the optimization pro- gramming model for the point-to-surface contact with friction and the fast optimization generalized minimal residual algorithm (GMRES(m)) significantly improve the analysis of such problems relative to the conven- tional BEM.展开更多
The velocity field in the Wu River at Chongqing was simulated using the shallow water equation implemented on clustered workstations. The parallel computing technique was used to increase the comput- ing power. The sh...The velocity field in the Wu River at Chongqing was simulated using the shallow water equation implemented on clustered workstations. The parallel computing technique was used to increase the comput- ing power. The shallow water equation was discretized to a linear system of equations with a direct parallel generalized minimum residual algorithm (GMRES) used to solve the linear system. Unlike other parallel GMRES methods, the direct GMRES method does not alter the sequential algorithm, but bases the paral- lelization on basic operations such as the matrix-vector product. The computed results agree well with ob- served results. The parallel computing technique significantly increases the solution speed for this large- scale problem.展开更多
基金Project supported by the National Natural Science Foundation of China(No.50075075).
文摘A mathematical program is proposed for the highly nonlinear problem involving frictional contact. A program-pattern using the fast multipole boundary element method (FM- BEM) is given for 3-D elastic contact with friction to replace the Monte Carlo method. A new optimized generalized minimal residual (GMRES) algorithm is presented. Numerical examples demonstrate the validity of the program-pattern optimization model for node-to-surface contact with friction. The GMRES algorithm greatly improves the computational efciency.
基金supported by the National Natural Science Foundation of China(Grant No.50678036)
文摘Small disturbance potential theory is widely used in solving aerodynamic problems with low Mach numbers,and it plays an important role in engineering design.Concerning structure wind engineering,the body of the structure is in a low velocity wind field,with a low viscosity of air and thin boundary layer,therefore,the tiny shear stress caused by the boundary layer can be ignored,only wind pressure being considered.In this paper,based on small disturbance potential theory,the fluid-structure interaction between the wind and membrane structure is analyzed by joint utilization of the boundary element method(BEM)and finite element method(FEM)through a loose-coupling procedure.However,the boundary of flow field to be calculated is not fully smooth,corners and edges still exist,so the discontinuous boundary element is introduced.Furthermore,because a large scale boundary element equation set with a nonsymmetrical coefficient matrix must be solved,this paper imports a preconditioning GMRES(the generalized minimum residual)iterative algorithm,which takes full advantage of the boundary element method.Several calculation examples have verified the correctness and soundness of the treatments mentioned above.
基金Supported by the National Natural Science Foundation of China(No. 50075075)
文摘This paper presents a new mathematical model for the highly nonlinear problem of frictional con- tact. A programming model, multipole boundary element method (BEM), was developed for 3-D elastic con- tact with friction to replace the Monte Carlo method. A numerical example shows that the optimization pro- gramming model for the point-to-surface contact with friction and the fast optimization generalized minimal residual algorithm (GMRES(m)) significantly improve the analysis of such problems relative to the conven- tional BEM.
基金Supported by the National Natural Science Foundation of China (Nos. 50379022 and 59979013)
文摘The velocity field in the Wu River at Chongqing was simulated using the shallow water equation implemented on clustered workstations. The parallel computing technique was used to increase the comput- ing power. The shallow water equation was discretized to a linear system of equations with a direct parallel generalized minimum residual algorithm (GMRES) used to solve the linear system. Unlike other parallel GMRES methods, the direct GMRES method does not alter the sequential algorithm, but bases the paral- lelization on basic operations such as the matrix-vector product. The computed results agree well with ob- served results. The parallel computing technique significantly increases the solution speed for this large- scale problem.
