Parallel hydrodynamic finite element model with an N-Best refining partition scheme

We enhance a robust parallel finite element model for coasts and estuaries cases with the use of N-Best refinement algorithms, in multilevel partitioning scheme. Graph partitioning is an important step to construct the parallel model, in which computation speed is a big concern. The partitioning strategy includes the division of the research domain into several semi-equal-sized sub-domains, minimizing the sum weight of edges between different sub-domains. Multilevel schemes for graph partitioning are divided into three phases: coarsening, partitioning, and uncoarsening. In the uncoarsening phase, many refinement algorithms have been proposed previously, such as KL, Greedy, and Boundary refinements. In this study, we propose an N-Best refinement algorithm and show its advantages in our case study of Xiamen Bay. Compared with original partitioning algorithm in previous models, the N-Best algorithm can speed up the computation by 1.9 times, and the simulation results are in a good match with the in-situ data.