A Load-balancing Tool for Structured Multi-block CFD Applications Applied to a Parallel Newton-Krylov Algorithm
Kwesi P. Apponsah · TSpace (University of Toronto) · 2012
For high-fidelity parallel computational fluid dynamic (CFD) simulations, multi-block grid methodology makes it possible to simulate flows around complex geometries. An automatic load-balancing tool is developed for a parallel Newton-Krylov algorithm that uses multi-block grids. The load-balancing tool uses a recursive edge bisection tool for splitting blocks to enforce load-balancing constraints. When homogeneous multi-block grids are used, an optional constraint is introduced to control block splitting. For heterogeneous multi-block grids, a block size constraint prevents smaller blocks from being split when the tool is started of with a smaller number of blocks than processors. The load-balancing tool is applied to three-dimensional multi-block grids for a Newton-Krylov solution process applied to the Euler and Reynolds-Averaged Navier-Stokes equations. For heterogeneous grids, significant reductions in turnaround time is obtained using the load-balancing tool than without a load-balancing tool. Finally, using the automatic tool, the scaling properties of the parallel Newton-Krylov algorithm are investigated.