PALM - A large-eddy simulation model performing on massively parallel computers

An existing code of a large-eddy simulation (LES) model for the study of tu rbulent processes in the atmospheric and oceanic boundary layer has been co mpletely recoded for use on massively parallel systems with distributed mem ory. Parallelization is achieved by two-dimensional domain decomposition an d communication is realized by the message passing interface (MPI). Periodi c boundary conditions, which are used in both horizontal directions, helped to minimize the parallelization effort. The performance of the new PAralle lized LES Model (PALM) is excellent on SGI/Cray-T3E systems and an almost l inear speed-up is achieved up to very large numbers of processors. Parallel ization strategy and model performance is discussed and validation experime nts as well as future applications are presented.