|Title||On parallel simulation of porous media flow|
|Project(s)||Department of High Performance Computing|
|Publication Type||Talks, invited|
|Year of Publication||2020|
|Location of Talk||Schlumberger Eureka Applied Math Special Interest Group Meeting|
|Type of Talk||Invited guest talk|
Parallel computing has become an indispensable tool for efficiently simulating the complicated multi-phase flows in porous media. To achieve good performance, we need to pay special attention to the foundation of parallelization, namely, how the computation is decomposed among the hardware processing units. The prerequisite mesh-partitioning problem boils down to an intricate interplay among load balance, communication overhead, and effectiveness of the resulting numerical calculation. Specifically, we quantitatively analyse the negative performance impact caused by non-contributing computations that are associated with the ``ghost computational cells" per subdomain. We also show how these non-contributing computations can be avoided by reordering the computational cells of each subdomain. Moreover, we propose a new graph-edge weighting scheme that can improve the mesh partitioning quality, aiming at a balance between handling the heterogeneity of geological properties and restricting the communication overhead. The findings are applied to the open-source Flow simulator from the OPM framework (https://opm-project.org), leading to substantial improvements of the parallel performance.