Open source extensions applied to meshing problems for KIVA 4

Abstract

ABSTRACT KIVA is a very successful software that was released around 1985. One of its advantages is the capacity to include computer routines made by the users. That is why it is mostly used for research and development and as a tool for simulation driven design and optimization of internal combustion engines. As with many CFD software, mesh generation with KIVA is time consuming when its own meshing program is used. This can be exacerbated in the case of complex geometries with a special mesh quality, or when unstructured meshes are needed. Commercially, there are several meshing tools that have features and are available for a price. But this study explores mesh generation for KIVA in four cases of difficult geometries using open source tools. This allows to control all the meshing steps and parameters like mesh refinement, anisotropy and directionality. The first case is a Venturi tube with diesel spray injected in the middle of the throat. The second one an unstructured mesh for an eccentric diesel piston bowl. The last two cases are hybrid meshing methods for an engine with two valves and a pre-chamber, and an engine with two valves and a non-axisymmetric bowl. All the cases were validated in KIVA. This study extends the applicability of KIVA in terms of possibilities and ease of mesh generation. Users can use their preferred CAD/mesh software and convert it to KIVA if the format is compatible with OpenFOAM. Accordingly, the presented methodology would reduce the time devoted to meshing.