A Parameter-Driven Physics-Informed Neural Network Framework for Solving Two-Parameter Singular Perturbation Problems Involving Boundary Layers
Pradanya Boro, Aayushman Raina, Srinivasan Natesan
TL;DR
This work tackles two-parameter singular perturbation problems with boundary-layer phenomena by extending parameter-asymptotic PINNs (PA-PINNs) to 1D and 2D elliptic and parabolic PDEs. It introduces a mesh-free PA-PINN framework that first captures the smooth component at large perturbations and then progressively reduces the perturbation parameters, guided by adaptive collocation point sampling and a weighted residual loss. Numerical experiments on a variety of 1D/2D problems demonstrate that PA-PINNs achieve higher accuracy and robustness than standard PINNs, Upwind FDM, and FEM, across different regimes determined by the ratio of $\varepsilon_1$ and $\varepsilon_2$, including complex boundary and corner layers. The approach eliminates the need for a priori knowledge of boundary-layer locations and widths, offering a scalable, architecture-agnostic method that can outperform traditional mesh-based methods in challenging layer-dominated regimes.
Abstract
In this article, our goal is to solve two-parameter singular perturbation problems (SPPs) in one- and two-dimensions using an adapted Physics-Informed Neural Networks (PINNs) approach. Such problems are of major importance in engineering and sciences as it appears in control theory, fluid and gas dynamics, financial modelling and so on. Solutions of such problems exhibit boundary and/or interior layers, which make them difficult to handle. It has been validated in the literature that standard PINNs have low accuracy and can't handle such problems efficiently. Recently Cao et. al \cite{cao2023physics} proposed a new parameter asymptotic PINNs (PA-PINNs) to solve one-parameter singularly perturbed convection-dominated problems. It was observed that PA-PINNs works better than standard PINNs and gPINNs in terms of accuracy, convergence and stability. In this article, for the first time robustness of PA-PINNs will be validated for solving two-parameter SPPs.
