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The smoothed molecular dynamics (SMD) method is an improvement of molecular dynamics (MD) method by introducing one set of background mesh and the mapping strategy between atoms and the mesh. Much larger time step size can be adopted in SMD method owing to the smooth effect for the high-frequency atomic motions. The SMD method shares the common feature of dual discretization with the meshfree material point method (MPM) that one group of particles and one set of background mesh are used. The SMD method also serves a seamless bridge coupling the MD region and the MPM region in the MD-SMD-MPM multiscale method. The coupling between MD and SMD is straightforward through atomic interactions between two regions, while the linkage between SMD and MPM can be achieved through common background mesh.

Parallel computation is desired especially for multiscale problems and problems of intensive loading. A parallel framework is developed in this talk for the SMD method. The message passing algorithms in the brick mode and the tiled mode of domain decomposition are both developed. The communication domain for the particles is firstly determined, and then the mesh nodes that are required for sending and receiving are automatically selected based the topologies of communication domains. An dynamic load balance strategy is also developed so that the waiting time is sharply reduced. Several typical examples demonstrate that the parallel framework is very efficient for problems with complex boundaries and material behaviors.

Molecular dynamics, Smoothed molecular dynamics, Material point method, Multiscale computation, Parallel computation