arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2203.01581math.NAcs.LGcs.NA
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一种用于求解曲面上偏微分方程的浅层物理信息神经网络

A shallow physics-informed neural network for solving partial differential equations on surfaces

National Central University(中央大学);National Yang Ming Chiao Tung University(国立阳明交通大学);National Center for Theoretical Sciences(理论科学研究中心);National Taiwan University(台湾大学)

Wei-Fan Hu, Yi-Jun Shih, Te-Sheng Lin, Ming-Chih Lai

AI总结:

本研究提出一种单隐藏层浅层物理信息神经网络,通过水平集函数改写曲面微分算子构建损失函数,可高效求解静态与演化曲面上的偏微分方程,精度良好且可应用于液滴表面活性剂输运模拟。

摘要:

本文提出一种浅层(单隐藏层)物理信息神经网络,用于求解静态和演化曲面上的偏微分方程。针对静态曲面情形,借助水平集函数可便捷计算曲面微分表达式中用到的曲面法向量和平均曲率。因此我们无需采用现有文献中的法向延拓约束,而是将曲面微分算子改写为传统笛卡尔微分算子的形式,并直接将其用于损失函数中。我们通过在复杂静态曲面上求解Laplace-Beltrami方程和表面扩散方程,对该方法开展了一系列性能研究。仅在隐藏层中使用中等数量的神经元,我们就能获得令人满意的预测结果。随后我们将该方法拓展,用于求解速度已知的演化曲面上的对流-扩散方程。为追踪曲面,我们额外引入一个预设隐藏层来约束曲面的拓扑结构,并利用网络学习曲面与预设拓扑之间的同胚映射。所提出的网络结构可同时实现曲面追踪和方程求解。数值结果再次表明,其精度与静态情形相当。作为应用,我们模拟了剪切流作用下液滴表面的表面活性剂输运过程,得到了若干符合物理规律的结果。

英文摘要:

In this paper, we introduce a shallow (one-hidden-layer) physics-informed neural network for solving partial differential equations on static and evolving surfaces. For the static surface case, with the aid of level set function, the surface normal and mean curvature used in the surface differential expressions can be computed easily. So instead of imposing the normal extension constraints used in literature, we write the surface differential operators in the form of traditional Cartesian differential operators and use them in the loss function directly. We perform a series of performance study for the present methodology by solving Laplace-Beltrami equation and surface diffusion equation on complex static surfaces. With just a moderate number of neurons used in the hidden layer, we are able to attain satisfactory prediction results. Then we extend the present methodology to solve the advection-diffusion equation on an evolving surface with given velocity. To track the surface, we additionally introduce a prescribed hidden layer to enforce the topological structure of the surface and use the network to learn the homeomorphism between the surface and the prescribed topology. The proposed network structure is designed to track the surface and solve the equation simultaneously. Again, the numerical results show comparable accuracy as the static cases. As an application, we simulate the surfactant transport on the droplet surface under shear flow and obtain some physically plausible results.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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