An algorithm to automatically convert 3D distorted finite elements into SPH(smoothed particle hydrodynamics)particles is proposed
which handles the problems with extreme distortions in impact dynamics. Mises stress criterion is taken
and the SPH-FEM(finite element method)conversion algorithm allows to use accurate and efficient FEM in the lower distortion regions
and SPH in the higher distortion regions. The perforation of a cylindrical steel projectile impacting a plate target is simulated in 3D using the SPH-FEM conversion algorithm. The good agreement between the computed result and the experimental observation shows the accuracy superiority of this algorithm. Corresponding conversion criterion should be chosen according to the material failure mode in engineering application.
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