Special Session 154: Optimization methods and numerical methods for nonlinear PDEs

Randomized Neural Networks for PDEs with Applications in MHD
Fei Wang
Xi`an Jiaotong University
Peoples Rep of China
Co-Author(s):    
Abstract:
The incompressible magnetohydrodynamic (MHD) equations are fundamental in modeling many physical and engineering phenomena. Yet their strong nonlinearity and two divergence-free constraints make them notoriously difficult to solve with traditional numerical methods. Recently, neural networks have gained attention for solving PDEs, but deep learning approaches often struggle: they are slow to train, get trapped in local minima, and only approximate mass conservation. In this talk, I will present a Structure-Preserving Randomized Neural Network (SP-RaNN) designed to overcome these challenges. SP-RaNN automatically and exactly enforces divergence-free conditions, avoids costly nonlinear optimization, and works in a space-time framework that preserves both physical and mathematical structures. The method linearizes the governing equations, discretizes them at collocation points, and solves the resulting system efficiently with least-squares techniques. Through applications to Navier-Stokes, Maxwell, and MHD equations, I will show that SP-RaNN achieves higher accuracy and efficiency than both traditional solvers and deep neural network methods.