Parellel Dynamic Load-Balancing for the Solution of Transient CFD Problems Using Adaptive Tetrahedral Meshes

This chapter focuses on the production of parallel adaptivity procedures—to be supplied in addition to the parallel computational fluid dynamics (CFD) solver—with particular emphasis on practical algorithms and routines for parallel dynamic load-balancing. The chapter presents a brief overview of a parallel algorithm for the refinement and de-refinement of tetrahedral meshes that are distributed across the memory of a parallel architecture. Based upon knowledge, it is possible to identify the desirable features of a mesh partitioning algorithm so as to ensure maximum efficiency of the parallel solver. Along with the details of such algorithm, the chapter provides a numerical example that is used to evaluate the presented algorithms. An Euler flow example has been cited that illustrates that the algorithm produces new partitions for significant efficiency improvement of the solver. A new parallel dynamic load-balancing algorithm has been developed for use in conjunction with an unstructured tetrahedral parallel adaptive solver for transient flow problems. The practical load-balancing algorithm is explained, followed by a discussion of its parallel implementation and an assessment of its performance on a transient shock problem.