Partial differential equations (PDEs) are often computationally challenging to solve, and in many settings many related PDEs must be be solved either at every timestep or for a variety of candidate boundary conditions, parameters, or geometric domains. We present a meta-learning based method which learns to rapidly solve problems from a distribution of related PDEs. We use meta-learning (MAML and LEAP) to identify initializations for a neural network representation of the PDE solution such that a residual of the PDE can be quickly minimized on a novel task. We apply our meta-solving approach to a nonlinear Poisson's equation, 1D Burgers' equation, and hyperelasticity equations with varying parameters, geometries, and boundary conditions. The resulting Meta-PDE method finds qualitatively accurate solutions to most problems within a few gradient steps; for the nonlinear Poisson and hyper-elasticity equation this results in an intermediate accuracy approximation up to an order of magnitude faster than a baseline finite element analysis (FEA) solver with equivalent accuracy. In comparison to other learned solvers and surrogate models, this meta-learning approach can be trained without supervision from expensive ground-truth data, does not require a mesh, and can even be used when the geometry and topology varies between tasks.
翻译:部分差异方程式(PDEs)往往在计算上具有挑战性,难以解决,在很多情况下,许多相关的PDE必须在每一个时间步骤或各种候选边界条件、参数或几何域中解决。我们提出了一个基于元学习的方法,学习如何迅速解决相关PDE分布中的问题。我们使用元学习(MAML和LEAP)为PDE解决方案的神经网络表达方式确定初始化程序,以便能够迅速将PDE的剩余部分在一项新任务中最小化。我们将我们的元解方法应用于非线性Poisson方程式、1D Burgers方程式和具有不同参数、地貌和边界条件的超弹性方程式。由此产生的Met-PDE方法在几个梯度步骤中为大多数问题找到质量准确的解决办法;对于非线性Poisson和超弹性方程式,它的结果是中间精度近至比基线定值要素分析(FEA)更近的排序。我们甚至将我们的元解法方法应用于其他已学的解解解解解方程式和定值模型、1DRgergersetalate等的公式,在不经过培训的地面模型中可以不需从高度模型中进行。