Hexahedral Mesh Matching: Converting non‐conforming hexahedral‐to‐hexahedral interfaces into conforming interfaces

Abstract

SUMMARYThis paper presents a new method, called Mesh Matching, for handling non-conforming hexahedralto-hexahedral interfaces for finite element analysis. Mesh Matching modifies the hexahedral element topology on one or both sides of the interface until there is a one-to-one pairing of finite element nodes, edges and quadrilaterals on the interface surfaces, allowing mesh entities to be merged into a single conforming mesh. Element topology is modified using hexahedral dual operations, including pillowing, sheet extraction, dicing and column collapsing. The primary motivation for this research is to simplify the generation of unstructured all-hexahedral finite element meshes. Mesh Matching relaxes global constraint propagation which currently hinders hexahedral meshing of large assemblies, and limits its extension to parallel processing. As a secondary benefit, by providing conforming mesh interfaces, Mesh Matching provides an alternative to artificial constraints such as tied contacts and multi-point constraints. The quality of the resultant conforming hexahedral mesh is high and the increase in number of elements is moderate.

Domain Decomposition Methods for Domain Composition Purpose: Chimera, Overset, Gluing and Sliding Mesh Methods

“…The third strategy, named Mesh Matching [78], deals with the issue of handling non-conforming hexahedral-to-hexahedral interfaces with the target of recovering a final all-hexahedral conformal mesh. This method locally modifies the topology of the hexahedral elements on one or on both sides of the interface surfaces, allowing the meshes to be merged into a conforming mesh across the interface.…”

A close look at valences in hexahedral element meshes

“…There are many published hexahedral mesh modification techniques such as grafting [6], mesh cutting [7], refinement [5,10], mesh matching [8], and coarsening [9]. Each of these techniques must make decisions as to where and what modifications will be made to effect the desired changes to the mesh.…”

“…In spite of the difficultly with hexahedral elemental topology optimization, there are many published hexahedral mesh modification techniques [5][6][7][8][9][10], such as adaptive refinement and coarsening, which take an input hexahedral mesh and modify it in some way to meet the analysts' objectives for the analysis. Most of these methods follow prescribed patterns or templates for mesh modification with little if any real-time decision making between potential topology changes.…”

Unstructured and Semi-Structured Hexahedral Mesh Generation Methods

“…On the contrary, other methods are designed to obtain a decomposition of an arbitrary geometry into simple blocks, see Section 4.1.2. Finally, it is worth to mention that there are several attempts to combine different hexahedral meshes into a single, conformal mesh, see [67][68][69]. In this way, the user can generate an hexahedral mesh on each part and then match them all to create a conformal mesh of the whole domain.…”