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Center for Nonlinear Studies |
A geometrically conservative arbitrary Lagrangian-Eulerian (ALE) scheme is presented with finite-volume method on general hybrid meshes. A moving mesh source term is derived from the geometric conservation and the physical conservation laws on arbitrarily moving meshes. The significance and effectiveness of the moving mesh source term regarding uniform flow preservation is demonstrated and also compared to a different finite-volume ALE formulation without such a source term. Temporal accuracy of the current ALE scheme does not deteriorate with the use of moving meshes. Navier-Stokes method is presented with ALE scheme utilizing general hybrid meshes containing all four types of three-dimensional elements; hexahedra, prisms, tetrahedra, and pyramids. The presence of grid interfaces between the multiple types of elements does not deteriorate accuracy of the solution. An upwind spatial discretization, and central schemes with different artificial dissipation operators are tested with the general hybrid meshes. Use of local blocks of hexahedra is evaluated in terms of accuracy and efficiency via simulations of high Reynolds number flows. The developed methods are implemented in parallel using partitioned general hybrid meshes and an efficient parallel communication scheme. Applicability of the presented ALE scheme is demonstrated by simulating vortex induced vibrations of a cylinder.