Hex-dominant mesh generation has recently received increasing attention from researchers and the simulation community due to its robustness compared to pure hex-mesh generation techniques. In this work, we present a first structure-informed simplification framework, aiming to reduce the number of non-hex cells from the hex-dominant meshes. Our framework extracts individual sub-structures via parallel relations from the input hex-dominant mesh, decomposes self-tangent and self-intersecting sub-structures for structure complexity control, and collapses certain sets of edges that are adjacent to particular non-hex cells to remove them. We design a filtering and ranking strategy to select edges and sub-structures for collapsing. To better understand the complexity of sub-structure configurations, we introduced a novel relation graph that captures the connections between edges and between edges and sub-structures. Additionally, we designed a smoothing algorithm for hex-dominant meshes that enhances hex cell quality, even in meshes containing various cell types. We evaluate the effectiveness of our framework by applying it to many hex-dominant meshes produced by three state-of-the-art hex-dominant meshing techniques. Our results achieve various levels of reduction in the number of non-hex cells of the input meshes, affirming the applicability of our framework for improving the hex-dominant meshes.
Si et al. (Thu,) studied this question.