Viscous Layer Meshes from Level Sets on Cartesian Meshes

Hybrid grid generation for viscous flow analysis

“…Zhang et al [5] Quad/Tri/Cartesian Advancing front method 2D Wang et al [6] Hexa/Tetra Advancing front method 3D Khawaja et al [10,11] Prism/Tetra Automatic receding 3D C advancing front method Dawes et al [8,9] Hexa/Cartesian Level set method 3D Gloth et al [12] Quad/Tri/Cartesian Level set method 2D Pattinson et al [13] Cartesian Cut-cell, dual-mesh 2D Ebeida et al [3] Quad/Tri Spatial decomposition We assume that the input object is given as a piecewise linear representation, such as the point sequence curves in 2D and triangular meshes in 3D. Let B = { 1 .…”

“…The pros and cons of each type are well discussed in the literatures such as Baker [2]. For this reason, a hybrid mesh consisting of a body-fitted structured mesh layer and an unstructured background mesh has gained the attention of CFD researchers for viscous flow analysis in recent years [3][4][5][6][7][8][9][10][11][12][13] including its use in several commercially available software programs such as VisCART, Harpoon, and GDT. However, a structured grid makes unnecessarily dense elements in areas far from focal objects to achieve the resolution required in the critical part of the domain.…”

“…Their work proposed an efficient time-integration algorithm for a moving object (unsteady) flow problem discretized with a hybrid grid and showed the advantages of using a hybrid grid. However, their work focuses on efficient numerical solutions, and the hybrid grid generation method is only briefly introduced Also, thinner portions of the viscous layer are generated at the concave regions to avoid local interferences of the propagating nodes Dawes et al [8,9] also introduced a hybrid mesh with a viscous layer based on Cartesian cells as background mesh. They projected the nodes on the Cartesian cells to the viscous layer and inserted unstructured cells where these two layers met to connect them, To do this work without skewed unstructured cells, the surface mesh should have a uniform size similar to Cartesian cells.…”

Compact upwind schemes on adaptive octrees

“…Numerical methods are tailored for the characteristics of each region, and then coupled across the surface-volume interface. Recent examples of these hybrid (finite-volume and finite-difference) schemes include elements of structured, unstructured, and Cartesian approaches [5][6][7]. The current work focuses solely on the volume off-body region, where reduced numerical stiffness allows the use of efficient and accurate explicit time-integration schemes.…”

Geometry/Grid Generation for 3D Multi-Disciplinary Simulations in Multi-Stage Turbomachinery

“…Yamane and Yamamoto 5 developed a procedure that used a combination of multi-block structured and overlaid grids for film-cooled turbine configurations. Dawes et al [6][7][8] developed an automated, unstructured-grid generation procedure using an octree-based cut-Cartesian method with a level-set geometry representation. Ni et al 9 demonstrated an unstructured-grid octree grid generation approach for turbine conjugate heat transfer simulation.…”