G-Adaptivity: optimised graph-based mesh relocation for finite element methods

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: Rowbottom, James, Maierhofer, Georg, Deveney, Teo, Mueller, Eike, Paganini, Alberto, Schratz, Katharina, Liò, Pietro, Schönlieb, Carola-Bibiane, Budd, Chris
Formato: Preprint
Publicado: 2024
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866909654874849280
author Rowbottom, James
Maierhofer, Georg
Deveney, Teo
Mueller, Eike
Paganini, Alberto
Schratz, Katharina
Liò, Pietro
Schönlieb, Carola-Bibiane
Budd, Chris
author_facet Rowbottom, James
Maierhofer, Georg
Deveney, Teo
Mueller, Eike
Paganini, Alberto
Schratz, Katharina
Liò, Pietro
Schönlieb, Carola-Bibiane
Budd, Chris
contents We present a novel, and effective, approach to achieve optimal mesh relocation in finite element methods (FEMs). The cost and accuracy of FEMs is critically dependent on the choice of mesh points. Mesh relocation (r-adaptivity) seeks to optimise the mesh geometry to obtain the best solution accuracy at given computational budget. Classical r-adaptivity relies on the solution of a separate nonlinear "meshing" PDE to determine mesh point locations. This incurs significant cost at remeshing, and relies on estimates that relate interpolation- and FEM-error. Recent machine learning approaches have focused on the construction of fast surrogates for such classical methods. Instead, our new approach trains a graph neural network (GNN) to determine mesh point locations by directly minimising the FE solution error from the PDE system Firedrake to achieve higher solution accuracy. Our GNN architecture closely aligns the mesh solution space to that of classical meshing methodologies, thus replacing classical estimates for optimality with a learnable strategy. This allows for rapid and robust training and results in an extremely efficient and effective GNN approach to online r-adaptivity. Our method outperforms both classical, and prior ML, approaches to r-adaptive meshing. In particular, it achieves lower FE solution error, whilst retaining the significant speed-up over classical methods observed in prior ML work.
format Preprint
id arxiv_https___arxiv_org_abs_2407_04516
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle G-Adaptivity: optimised graph-based mesh relocation for finite element methods
Rowbottom, James
Maierhofer, Georg
Deveney, Teo
Mueller, Eike
Paganini, Alberto
Schratz, Katharina
Liò, Pietro
Schönlieb, Carola-Bibiane
Budd, Chris
Machine Learning
Numerical Analysis
We present a novel, and effective, approach to achieve optimal mesh relocation in finite element methods (FEMs). The cost and accuracy of FEMs is critically dependent on the choice of mesh points. Mesh relocation (r-adaptivity) seeks to optimise the mesh geometry to obtain the best solution accuracy at given computational budget. Classical r-adaptivity relies on the solution of a separate nonlinear "meshing" PDE to determine mesh point locations. This incurs significant cost at remeshing, and relies on estimates that relate interpolation- and FEM-error. Recent machine learning approaches have focused on the construction of fast surrogates for such classical methods. Instead, our new approach trains a graph neural network (GNN) to determine mesh point locations by directly minimising the FE solution error from the PDE system Firedrake to achieve higher solution accuracy. Our GNN architecture closely aligns the mesh solution space to that of classical meshing methodologies, thus replacing classical estimates for optimality with a learnable strategy. This allows for rapid and robust training and results in an extremely efficient and effective GNN approach to online r-adaptivity. Our method outperforms both classical, and prior ML, approaches to r-adaptive meshing. In particular, it achieves lower FE solution error, whilst retaining the significant speed-up over classical methods observed in prior ML work.
title G-Adaptivity: optimised graph-based mesh relocation for finite element methods
topic Machine Learning
Numerical Analysis
url https://arxiv.org/abs/2407.04516