An improved local remeshing algorithm for moving boundary problems

Abstract

Three issues are tackled in this study to improve the robustness of local remeshing techniques. Firstly, the local remeshing region (hereafter referred to as 'hole') is initialized by removing low-quality elements and then continuously expanded until a certain element quality is reached after remeshing. The effect of the number of the expansion cycle on the hole size and element quality after remeshing is experimentally analyzed. Secondly, the grid sources for element size control are attached to moving bodies and will move along with their host bodies to ensure reasonable grid resolution inside the hole. Thirdly, the boundary recovery procedure of a Delaunay grid generation approach is enhanced by a new grid topology transformation technique (namely shell transformation) so that the new grid created inside the hole is therefore free of elements of extremely deformed/skewed shape, whilst also respecting the hole boundary. The proposed local remeshing algorithm has been integrated with an in-house unstructured grid-based simulation system for solving moving boundary problems. The robustness and accuracy of the developed local remeshing technique are successfully demonstrated via industry-scale applications for complex flow simulations. ARTICLE HISTORY

Hybrid grid generation for viscous flow simulations in complex geometries

“…Since this issue is not involved in this study, the discussion is beyond the scope of this paper. Interested readers are referred to [30,31].…”

Improved boundary constrained tetrahedral mesh generation by shell transformation

“…In hybrid mesh generation for viscous simulations [25][26][27], the boundary layer mesher may introduce low-quality faces that are parts of the inputs for the tetrahedral mesher. In simulations of moving boundary problems [28][29][30], mesh faces were stretched in the mesh movement process, and some of them may appear in the boundary of the hole to be remeshed. To tackle the issue of minimizing the usage of Steiner points during boundary recovery is undoubtedly beneficial for these applications.…”

Innovative Meshing Strategies for Bearing Lubrication Simulations

“…To partially overcome this problem, in the past several attempts were made. In particular, rotating reference frames [4,5], innovative partitioning strategies [6,7] and, mostly, mesh-handling algorithms [8][9][10][11] have been developed and applied in order to reduce the simulation effort.…”