Large-scale parallel flow analysis based on free mesh method: a virtually meshless method

Abstract In this paper, large-scale parallel computing based on a virtually meshless method called the ‘free mesh method’ for incompressible viscous flow with three-million D.O.Fs or one-million nodes is presented. By using the free-mesh method, a seamless system from the stage of nodal information input without node-element connectivity information to the stage of the system equations solver is successfully developed. The system can compute the global mass, advection, diffusion, gradient and divergence matrices node-by-node independently from only nodal information on a parallel computer. With techniques of node generation based on nodal density control and a kind of hash sorting method for search nodes, a lid-driven cavity problem having three-million D.O.Fs can be successfully solved. In the problem, the process of constructing system equations from nodal information by the free-mesh method, requires about 142 s using 64 processors of the Hitachi SR2201.

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