Abstract
In this paper, we present a hybrid grid generation approach for viscous flow simulations by marching a surface triangulation on viscous walls along certain directions. Focuses are on the computing strategies used to determine the marching directions and distances since these strategies determine the quality of the resulting elements and the reliability of the meshing procedure to a large extent. With respect to marching directions, three strategies featured with different levels of efficiencies and robustness performance are combined to compute the initial normals at front nodes to balance the trade-off between efficiency and robustness. A novel weighted strategy is used in the normal smoothing scheme, which evidently reduces the possibility of early stop of front generation at complex corners. With respect to marching distances, the distance settings at concave and/or convex corners are locally adjusted to smooth the front shape at first; a further adjustment is then conducted for front nodes in the neighbourhood of gaps between opposite viscous boundaries. These efforts, plus other special treatments such as multi-normal generation and fast detection of local/global intersection, as a whole enable the setup of a hybrid mesher that could generate qualitied viscous grids for geometries with industry-level complexities.
Highlights
For RANS computations involving complex geometries, a challenging task is the generation of high-quality RANS meshes
In a prismatic hybrid mesh, the near field of viscous walls is configured with layered prismatic elements to resolve high flow gradients normal to the walls, whereas the remaining domain is usually filled with an unstructured mesh
The generation of a hybrid prismatic mesh usually consists of two individual meshing steps: boundary layer mesh generation and unstructured mesh generation
Summary
For RANS computations involving complex geometries, a challenging task is the generation of high-quality RANS meshes. Compared with the mature unstructured mesh generation and Cartesian mesh generation, the generation of boundary layer meshes still gives rise to numerous difficulties and is the main challenge in generating the entire prismatic hybrid mesh Among those difficulties, those induced by the computations of marching directions and marching distances should be highlighted because both computations determine the quality of the resulting elements and the reliability of the meshing procedure to a large extent. A practically useful hybrid mesh generation scheme should take the quality of the resulting elements and the reliability of the meshing procedure as the primary consideration Following this principle, we proposed several novel computing strategies for marching directions and marching distances.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
