论文标题
从头开始学习不可压缩的流体动力学 - 朝着概括的快速,可区分的流体模型
Learning Incompressible Fluid Dynamics from Scratch -- Towards Fast, Differentiable Fluid Models that Generalize
论文作者
论文摘要
快速,稳定的流体模拟是从计算机生成的图像到计算机辅助设计的应用程序的重要先决条件。但是,解决不可压缩流体的部分微分方程是一项具有挑战性的任务,传统的数值近似方案的计算成本很高。最近的基于深度学习的方法有望大大加速,但不会推广到新的流体域,需要流体模拟数据进行培训或依靠复杂的管道,将流体模拟的主要部分外包到传统方法。 在这项工作中,我们提出了一种新型的物理受限的训练方法,该方法将概括为新的流体域,不需要流体模拟数据,并允许卷积神经网络从单个正向通过时在时间t + dt的随后状态绘制流体状态。这简化了训练和评估神经流体模型的管道。训练后,该框架产生了能够快速流体模拟的模型,并且可以处理各种流体现象,包括Magnus效应和Karman Vortex街道。我们提出了一个交互式实时演示,以显示我们训练的模型的速度和概括功能。此外,训练有素的神经网络是有效的可区分流体求解器,因为它们提供了可区分的更新步骤,以及时推动流体模拟。我们在概念验证的最佳控制实验中利用了这一事实。从计算速度和准确性方面,我们的模型大大优于最近可区分的流体求解器。
Fast and stable fluid simulations are an essential prerequisite for applications ranging from computer-generated imagery to computer-aided design in research and development. However, solving the partial differential equations of incompressible fluids is a challenging task and traditional numerical approximation schemes come at high computational costs. Recent deep learning based approaches promise vast speed-ups but do not generalize to new fluid domains, require fluid simulation data for training, or rely on complex pipelines that outsource major parts of the fluid simulation to traditional methods. In this work, we propose a novel physics-constrained training approach that generalizes to new fluid domains, requires no fluid simulation data, and allows convolutional neural networks to map a fluid state from time-point t to a subsequent state at time t + dt in a single forward pass. This simplifies the pipeline to train and evaluate neural fluid models. After training, the framework yields models that are capable of fast fluid simulations and can handle various fluid phenomena including the Magnus effect and Karman vortex streets. We present an interactive real-time demo to show the speed and generalization capabilities of our trained models. Moreover, the trained neural networks are efficient differentiable fluid solvers as they offer a differentiable update step to advance the fluid simulation in time. We exploit this fact in a proof-of-concept optimal control experiment. Our models significantly outperform a recent differentiable fluid solver in terms of computational speed and accuracy.