Massively parallel grid generation on HPC systems

The automatic grid generation on high performance computers is a challenging task under the restriction of computational power and memory availability. The increasing demand for high grid resolutions to simulate complex flow configurations necessitates parallel grid generation on multicore machines with distributed memory. In this study, a new robust algorithm to automatically generate hierarchical Cartesian meshes on distributed multicore HPC systems with multiple levels of refinement is presented. The number of cells is only restricted by the number of available cores and memory. The algorithm efficiently realizes a computational domain decompositioning for an arbitrary number of cores based on a Hilbert curve. The grids are efficiently stored and accessed via a high capacity parallel I/O method. The efficiency of the approach is demonstrated by considering human nasal cavity and internal combustion engine flow problems.