Abstract High parallel efficiency for large-scale coupled multiphysics simulations requires the computational load to be evenly distributed among all compute cores. For complex applications and massively parallel computations, even minor load imbalances can have a severe impact on the overall performance and resource usage. Exemplarily for a volume-coupled multiphysics simulation, a direct-hybrid method is considered, in which a CFD and a CAA simulation are performed concurrently on the same parallel subdomains. For differing load compositions on each subdomain, accurate computational weights for CFD and CAA cells must be known to determine an efficient domain decomposition. Therefore, a dynamic load balancing scheme is presented, which allows to increase the efficiency of complex coupled simulations with non-trivial domain decompositions. A fully-coupled three-dimensional jet simulation with approximately 300 million degrees of freedom demonstrates the effectiveness of the approach to reduce load imbalances. A detailed performance analysis substantiates the necessity of dynamic load balancing. Furthermore, the results of a strong scaling experiment show the benefit of load balancing to be proportional to the degree of parallelism. In addition, it is shown that the approach allows to attenuate imbalances also for parallel computations on heterogeneous computing hardware. The acoustic field of a chevron nozzle will also be discussed.

中文翻译：

---

用于直接耦合多物理场仿真的动态负载平衡

摘要 大规模耦合多物理场仿真的高并行效率要求计算负载在所有计算核心之间均匀分布。对于复杂的应用程序和大规模并行计算，即使是很小的负载不平衡也会对整体性能和资源使用产生严重影响。作为体积耦合多物理场仿真的示例，考虑了直接混合方法，其中 CFD 和 CAA 仿真在相同的并行子域上同时执行。对于每个子域上的不同负载组合，必须知道 CFD 和 CAA 单元的准确计算权重，以确定有效的域分解。因此，提出了一种动态负载平衡方案，该方案允许通过非平凡域分解提高复杂耦合模拟的效率。具有大约 3 亿个自由度的全耦合三维射流模拟证明了该方法在减少负载不平衡方面的有效性。详细的性能分析证实了动态负载平衡的必要性。此外，强扩展实验的结果表明负载平衡的好处与并行度成正比。此外，还表明该方法还可以减轻异构计算硬件上的并行计算的不平衡。还将讨论 V 形喷嘴的声场。此外，强扩展实验的结果表明负载平衡的好处与并行度成正比。此外，还表明该方法还可以减轻异构计算硬件上的并行计算的不平衡。还将讨论 V 形喷嘴的声场。此外，强扩展实验的结果表明负载平衡的好处与并行度成正比。此外，还表明该方法还可以减轻异构计算硬件上的并行计算的不平衡。还将讨论 V 形喷嘴的声场。