High-fidelity flow simulations are indispensable when analyzing systems exhibiting multiphase flow phenomena. The accuracy of multiphase flow simulations is strongly contingent upon the finest mesh resolution used to represent the fluid-fluid interfaces. However, the increased resolution comes at a higher computational cost. In this work, we propose algorithmic advances that aim to reduce the computational cost without compromising on the physics by selectively detecting key regions of interest (droplets/filaments) that require significantly higher resolution. The framework uses an adaptive octree-based meshing framework that is integrated with PETSc's linear algebra solvers. We demonstrate scaling of the framework up to 114,688 processes on TACC's Frontera. Finally, we deploy the framework to simulate one of the most resolved simulations of primary jet atomization. This simulation -- equivalent to 35 trillion grid points on a uniform grid -- is 64 times larger than the current state-of-the-art simulations and provides unprecedented insights into an important flow physics problem with a diverse array of engineering applications.

翻译：高保真度的流体模拟对于分析展现多相流现象的系统是必不可少的。多相流模拟的准确性在很大程度上取决于用于表示流体-流体界面的最细网格分辨率。但是，增加的分辨率会引起更高的计算成本。在本论文中，我们提出了算法进步，旨在通过有选择地检测需要更高分辨率的关键兴趣区域（液滴/细丝）来减少计算成本，而不会在物理上妥协。该框架使用自适应的八叉树网格框架，该框架已经与PETSc的线性代数求解器集成。我们展示了该框架在TACC的Frontera上扩展到114,688个进程。最后，我们将该框架部署到模拟primarry jet atomization的状态，该模拟相当于一个均匀网格上的35万亿网格点，比当前最先进的模拟大64倍，并提供了对具有各种工程应用的重要流体力学问题的前所未有的见解。