论文标题
与物理信息的神经网络的混合有限差异求解复杂几何形状的PDE
Hybrid Finite Difference with the Physics-informed Neural Network for solving PDE in complex geometries
论文作者
论文摘要
物理知识的神经网络(PINN)通过通过自动分化(AD)捕获物理限制作为训练损失函数的一部分来有效地解决部分微分方程(PDE)。这项研究提出了与物理知识神经网络(HFD-PINN)的混合有限差异,以充分使用域知识。主要思想是在PINN的框架中使用有限差异方法(FDM)而不是AD。特别是,我们在复杂边界和其他域中使用AD。混合学习模型在实验中显示出令人鼓舞的结果。要在复杂边界域中使用FDM并避免产生背景网格,我们提出了HFD-PINN-SDF方法,该方法在随机点上局部使用有限差方案。另外,签名的距离函数用于避免越过域边界的差异方案。在本文中,我们证明了我们提出的方法的性能,并将结果与泊松方程(汉堡方程)的搭配点的不同数量进行了比较。我们还选择了几种不同的有限差异方案,包括紧凑型差异法(CDM)和曲柄 - 尼科尔森方法(CNM)来验证HFD-PINN的鲁棒性。我们将热传导问题和不规则结构域上的传热问题作为证明我们框架功效的例子。总而言之,在求解复杂几何形状的PDE时,HFD-PINN,尤其是HFD-PINN-SDF更具启发性和有效性。
The physics-informed neural network (PINN) is effective in solving the partial differential equation (PDE) by capturing the physics constraints as a part of the training loss function through the Automatic Differentiation (AD). This study proposes the hybrid finite difference with the physics-informed neural network (HFD-PINN) to fully use the domain knowledge. The main idea is to use the finite difference method (FDM) locally instead of AD in the framework of PINN. In particular, we use AD at complex boundaries and the FDM in other domains. The hybrid learning model shows promising results in experiments. To use the FDM locally in the complex boundary domain and avoid the generation of background mesh, we propose the HFD-PINN-sdf method, which locally uses the finite difference scheme at random points. In addition, the signed distance function is used to avoid the difference scheme from crossing the domain boundary. In this paper, we demonstrate the performance of our proposed methods and compare the results with the different number of collocation points for the Poisson equation, Burgers equation. We also chose several different finite difference schemes, including the compact finite difference method (CDM) and crank-nicolson method (CNM), to verify the robustness of HFD-PINN. We take the heat conduction problem and the heat transfer problem on the irregular domain as examples to demonstrate the efficacy of our framework. In summary, HFD-PINN, especially HFD-PINN-sdf, are more instructive and efficient, significantly when solving PDEs in complex geometries.