🤖 AI Summary
To address the low computational efficiency of numerical simulation and optimization for partial differential equations (PDEs) in multi-query scenarios, this work proposes a preconditioned architecture that synergistically integrates the finite element method (FEM) with physics-informed neural networks (PINNs) for direct solution of the incompressible Navier–Stokes equations and their inverse problems. Our method embeds FEM stiffness and mass matrices into the network architecture and enforces physically consistent preconditioning, unifying regularization, convergence guarantees, and interpretability. It further incorporates a weak-form-driven loss function, physics-constrained network design, and hybrid forward/backward gradient optimization. On Stokes and unsteady Navier–Stokes benchmark problems, the approach achieves spectral accuracy; for inverse problems, it reduces reconstruction error by over 40% and significantly improves training stability.