Incremental Decomposition for Hex-Meshing in CAD Using Virtual Topology

This paper presents methods for preparing a geometry model for finite element mesh generation in a Mechanical Computer-Aided Design (MCAD) environment. It works by creating a new representation of the model through the application of virtual topology operators. The resulting “analysis topology” description is used to abstract the analysis model, enabling automated tools and experts to apply an incremental strategy to decompose the model for meshing, without modifying the original CAD model. This work also demonstrated how virtual topology enables the integration of multiple model decomposition tools to expand the capabilities of the hosting CAD environment, providing support for more meshing strategies and more freedom in how they are applied, while bridging the gap between the CAD and analysis models. Herein, the virtual topology operators used to decompose the model are checked and propagated based on the required mesh constraints to ensure the resulting mesh is conformal at the interfaces. Finally, the methods required to decompose the original CAD model using the analysis topology description and “virtual geometry curves” are presented, enabling downstream automation of the mesh.