A polytree based coupling method for non-matching meshes in 3D

Abstract

The coupling of non-matching meshes is of great interest in the field of computational mechanics. It reduces meshing burden by allowing users to divide a problem domain into several simpler subdomains and generate meshes for them independently. In this paper, a coupling method using arbitrary polyhedron elements is presented. On the interface of two non-matching meshes, a new surface mesh of polygon elements is constructed by merging the non-matching meshes. A shifting procedure is designed to prevent the distortion of surface elements. The polyhedron elements connected to the interface are modified by replacing their faces on the interface with the new polygon elements, leading to matching discretization on the interface. The modified polyhedron elements are modeled by the scaled boundary finite element method and no further volume discretization is required. No interface constraints or special shape functions are required in the analysis. Seven numerical examples are presented to demonstrate the versatility and robustness of the proposed procedure. Convergence behavior is also examined.