Space-Time Multigrid Methods Suitable for Topology Optimisation of Transient Heat Conduction

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Appel, Magnus, Alexandersen, Joe
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866912376772624384
author Appel, Magnus
Alexandersen, Joe
author_facet Appel, Magnus
Alexandersen, Joe
contents This paper presents Space-Time MultiGrid (STMG) methods which are suitable for performing topology optimisation of transient heat conduction problems. The proposed methods use a pointwise smoother and uniform Cartesian space-time meshes. For problems with high contrast in the diffusivity, it was found that it is beneficial to define a coarsening strategy based on the geometric mean of the minimum and maximum diffusivity. However, other coarsening strategies may be better for other smoothers. Several methods of discretising the coarse levels were tested. Of these, it was best to use a method which averages the thermal resistivities on the finer levels. However, this was likely a consequence of the fact that only one spatial dimension was considered for the test problems. A second coarsening strategy was proposed which ensures spatial resolution on the coarse grids. Mixed results were found for this strategy. The proposed STMG methods were used as a solver for a one-dimensional topology optimisation problem. In this context, the adjoint problem was also solved using the STMG methods. The STMG methods were sufficiently robust for this application, since they converged during every optimisation cycle. It was found that the STMG methods also work for the adjoint problem when the prolongation operator only sends information forwards in time, even although the direction of time for the adjoint problem is backwards.
format Preprint
id arxiv_https___arxiv_org_abs_2505_10168
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Space-Time Multigrid Methods Suitable for Topology Optimisation of Transient Heat Conduction
Appel, Magnus
Alexandersen, Joe
Computational Engineering, Finance, and Science
65K10, 65M55, 65M22, 65M32, 80M10, 80M50
This paper presents Space-Time MultiGrid (STMG) methods which are suitable for performing topology optimisation of transient heat conduction problems. The proposed methods use a pointwise smoother and uniform Cartesian space-time meshes. For problems with high contrast in the diffusivity, it was found that it is beneficial to define a coarsening strategy based on the geometric mean of the minimum and maximum diffusivity. However, other coarsening strategies may be better for other smoothers. Several methods of discretising the coarse levels were tested. Of these, it was best to use a method which averages the thermal resistivities on the finer levels. However, this was likely a consequence of the fact that only one spatial dimension was considered for the test problems. A second coarsening strategy was proposed which ensures spatial resolution on the coarse grids. Mixed results were found for this strategy. The proposed STMG methods were used as a solver for a one-dimensional topology optimisation problem. In this context, the adjoint problem was also solved using the STMG methods. The STMG methods were sufficiently robust for this application, since they converged during every optimisation cycle. It was found that the STMG methods also work for the adjoint problem when the prolongation operator only sends information forwards in time, even although the direction of time for the adjoint problem is backwards.
title Space-Time Multigrid Methods Suitable for Topology Optimisation of Transient Heat Conduction
topic Computational Engineering, Finance, and Science
65K10, 65M55, 65M22, 65M32, 80M10, 80M50
url https://arxiv.org/abs/2505.10168