Estimating fluid dynamics is classically done through the simulation and integration of numerical models solving the Navier-Stokes equations, which is computationally complex and time-consuming even on high-end hardware. This is a notoriously hard problem to solve, which has recently been addressed with machine learning, in particular graph neural networks (GNN) and variants trained and evaluated on datasets of static objects in static scenes with fixed geometry. We attempt to go beyond existing work in complexity and introduce a new model, method and benchmark. We propose EAGLE, a large-scale dataset of 1.1 million 2D meshes resulting from simulations of unsteady fluid dynamics caused by a moving flow source interacting with nonlinear scene structure, comprised of 600 different scenes of three different types. To perform future forecasting of pressure and velocity on the challenging EAGLE dataset, we introduce a new mesh transformer. It leverages node clustering, graph pooling and global attention to learn long-range dependencies between spatially distant data points without needing a large number of iterations, as existing GNN methods do. We show that our transformer outperforms state-of-the-art performance on, both, existing synthetic and real datasets and on EAGLE. Finally, we highlight that our approach learns to attend to airflow, integrating complex information in a single iteration.
翻译:估计流体动力学经典上是通过数值模型的模拟和积分来解决纳维-斯托克斯方程的,即使在高端硬件上也是计算复杂且耗时的。这是一个非常难解决的问题,最近使用机器学习来解决,特别是使用图神经网络(GNN)和变种,训练和评估静态场景中的静态物体数据集。我们试图在复杂性方面超越现有研究,并引入新的模型、方法和基准。我们提出了EAGLE,这是一个大规模的数据集,包含了1.1百万2D网格,这些网格是由移动流源与非线性场景结构相互作用引起的不稳定流体动力学模拟的结果,由600个不同类型的场景组成。为了对具有挑战性的EAGLE数据集进行未来预测,我们引入了一种新的网格变换器。它利用节点聚类、图汇聚和全局注意力,在不需要大量迭代的情况下学习空间上相隔较远的数据点之间的长程依赖关系,如现有的GNN方法所做的那样。我们证明了我们的变换器在现有的合成和真实数据集以及EAGLE上的表现优于现有的最先进表现。最后,我们强调,我们的方法学习关注气流,将复杂信息集成到单次迭代中。