• Dynamic mesh adaption on unstructured grids is a powerful tool for computing unsteady 3D problems that require grid modifications to efficiently resolve solution features.
• By locally refining and coarsening the mesh to capture flowfield phenomena of interest, such procedures make standard computational methods more cost effective.
• For example, Fluent adapts the mesh based on:
- Gradients of flow or user-defined variables.
- Isovalues of flow or user-defined variables.
- All cells on a boundary.
- All cells in a region.
- Cell volumes or volume changes.
- y+ (see below for the definition of y+) in cells adjacent to walls.
• For flow-aligned geometries, quad/hex meshes can provide higher-quality solutions with fewer cells/nodes than a comparable tri/tet mesh
- Quad/Hex meshes show reduced numerical diffusion when the mesh is aligned with the flow.
- It does require more effort to generate a quad/hex mesh
• Meshing tools designed for a specific application can streamline the process of creating a quad/hex mesh for some geometries.
• For complex geometries, quad/hex meshes show no numerical advantage, and you can save meshing effort by using a tri/tet mesh or hybrid mesh
- Quick to generate
- Flow is generally not aligned with the mesh
• Hybrid meshes typically combine tri/tet elements with other elements in selected Regions
- For example, use wedge/prism elements to resolve boundary layers
- More efficient and accurate than tri/tet alone