Multi-body separation simulation with an improved general mesh deformation method

Abstract This paper presents an improved general mesh deformation method and its application in multi-body separation simulation. Intelligent Laplacian smoothing algorithm is combined with previously developed radial basis function (RBF) mesh deform technology to avoid mesh quality decreasing and topology damaging in successive large mesh deformation. In the intelligent Laplacian smoothing algorithm, mesh qualities of tetrahedron, triangular prism, hexahedron and pyramid are evaluated by a unified standard which is used to setup the criterion of the smoothing onset. This improved mesh deformation methodology is integrated into a solver of Navier–Stokes equations coupled with six degrees of freedom (6-DOF) moving equations. The store separation trajectory of a generic wing, pylon, and store configuration is successfully simulated to validate the ability of improved mesh deformation methodology in dealing with large magnitude of relative motion among multiple moving boundaries. Numerical simulation results agree well with experimental data, which states that the accuracy and robustness of the above numerical methods can reach the requirement of describing the traces of multi-body separation.

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