What we all know to be true in practice is that a good mesh helps the computational fluid dynamics (CFD) solver converge to the correct answer while minimizing the computer resources expended. Stated differently, most every decent solver will yield an accurate answer with a good mesh, but it takes the most robust of solvers to get an answer on a bad mesh.
Hybrid mesh adopted by Castle is perfectly suited for complex-geometry flow simulations and is adopted by several modern CFD applications. They consist of prisms and/or regular hexahedra covering the center of the casting, while deformed hexahedra discretize the surface of the domain.
– the internal hexahedral mesh gives more accurate solutions.
– even with “big” elements, the surface mesh density is high enough to capture all relevant flow features;
– the external refined and deformed hexahedrons allow to discretize the geometry by following exactly the shape of the model. The visual result is very similar to the CAD model without the need to create a very refined mesh.
Additionally Castle includes a simple but very effective system for local mesh refinement of sensitive regions. The user is requested to select only the areas where the calculation needs to increase the local accuracy (i.e. gates, overflows gates, details and thin walls) and the software automatically adapts the mesh size by following user-defined meshing presets.