Learnable Viscosity Modulation in Physics-Informed Neural Networks for Incompressible Flow Reconstruction

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Xu, Ke, Tao, Ze, Liu, Fujun
Format: Preprint
Published: 2026
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866908919267328000
author Xu, Ke
Tao, Ze
Liu, Fujun
author_facet Xu, Ke
Tao, Ze
Liu, Fujun
contents Accurately and stably solving the incompressible Navier--Stokes equations with physics-informed neural networks (PINNs) remains challenging, particularly for sparse or noisy observations and for flow regimes in which the local balance among convection, diffusion, and pressure is difficult to capture. To address this issue, we propose a framework, denoted as LVM-PINN, which incorporates a learnable viscosity modulation (LVM) mechanism into the PINN residual. Specifically, the model predicts a spatiotemporal scalar field that is embedded directly into the viscous diffusion term of the momentum equations, thereby enabling adaptive modulation of the local dissipation strength during training. This modification improves optimization stability while enhancing the representation of complex flow structures. The effect of the proposed mechanism is further examined through a controlled ablation setting with an otherwise unchanged network architecture, as well as through comparisons with GRU- and residual-attention-based backbone baselines. Numerical experiments on two-dimensional benchmark problems, including the Kovasznay flow and two manufactured forcing flows, show that the proposed framework yields more stable training behavior and more accurate flow reconstruction under sparse and noisy data conditions.
format Preprint
id arxiv_https___arxiv_org_abs_2603_27496
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Learnable Viscosity Modulation in Physics-Informed Neural Networks for Incompressible Flow Reconstruction
Xu, Ke
Tao, Ze
Liu, Fujun
Fluid Dynamics
35Q30 (Primary) 68T07, 76D05 (Secondary)
I.6.5
Accurately and stably solving the incompressible Navier--Stokes equations with physics-informed neural networks (PINNs) remains challenging, particularly for sparse or noisy observations and for flow regimes in which the local balance among convection, diffusion, and pressure is difficult to capture. To address this issue, we propose a framework, denoted as LVM-PINN, which incorporates a learnable viscosity modulation (LVM) mechanism into the PINN residual. Specifically, the model predicts a spatiotemporal scalar field that is embedded directly into the viscous diffusion term of the momentum equations, thereby enabling adaptive modulation of the local dissipation strength during training. This modification improves optimization stability while enhancing the representation of complex flow structures. The effect of the proposed mechanism is further examined through a controlled ablation setting with an otherwise unchanged network architecture, as well as through comparisons with GRU- and residual-attention-based backbone baselines. Numerical experiments on two-dimensional benchmark problems, including the Kovasznay flow and two manufactured forcing flows, show that the proposed framework yields more stable training behavior and more accurate flow reconstruction under sparse and noisy data conditions.
title Learnable Viscosity Modulation in Physics-Informed Neural Networks for Incompressible Flow Reconstruction
topic Fluid Dynamics
35Q30 (Primary) 68T07, 76D05 (Secondary)
I.6.5
url https://arxiv.org/abs/2603.27496