On the finite element approximation of a semicoercive stokes variational inequality arising in glaciology
Stokes variational inequalities arise in the formulation of glaciological problems involving contact. We consider the problem of a two-dimensional marine ice sheet with a grounding line, although the analysis presented here is extendable to other contact problems in glaciology, such as that of subgl...
Published in: | SIAM Journal on Numerical Analysis |
---|---|
Main Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Society for Industrial and Applied Mathematics
2022
|
Subjects: | |
Online Access: | https://doi.org/10.1137/21M1437640 https://ora.ox.ac.uk/objects/uuid:c607888d-f850-4ca2-99f9-19607bff6435 |
id |
ftuloxford:oai:ora.ox.ac.uk:uuid:c607888d-f850-4ca2-99f9-19607bff6435 |
---|---|
record_format |
openpolar |
spelling |
ftuloxford:oai:ora.ox.ac.uk:uuid:c607888d-f850-4ca2-99f9-19607bff6435 2023-05-15T16:41:01+02:00 On the finite element approximation of a semicoercive stokes variational inequality arising in glaciology de Diego, G Farrell, P Hewitt, I 2022-11-11 https://doi.org/10.1137/21M1437640 https://ora.ox.ac.uk/objects/uuid:c607888d-f850-4ca2-99f9-19607bff6435 eng eng Society for Industrial and Applied Mathematics doi:10.1137/21M1437640 https://ora.ox.ac.uk/objects/uuid:c607888d-f850-4ca2-99f9-19607bff6435 https://doi.org/10.1137/21M1437640 info:eu-repo/semantics/openAccess Journal article 2022 ftuloxford https://doi.org/10.1137/21M1437640 2023-03-16T23:06:11Z Stokes variational inequalities arise in the formulation of glaciological problems involving contact. We consider the problem of a two-dimensional marine ice sheet with a grounding line, although the analysis presented here is extendable to other contact problems in glaciology, such as that of subglacial cavitation. The analysis of this problem and its discretisation is complicated by the nonlinear rheology commonly used for modelling ice, the enforcement of a friction boundary condition given by a power law, and the presence of rigid modes in the velocity space, which render the variational inequality semicoercive. In this work, we consider a mixed formulation of this variational inequality involving a Lagrange multiplier and provide an analysis of its finite element approximation. Error estimates in the presence of rigid modes are obtained by means of a specially-built projection operator onto the subspace of rigid modes and a Korn-type inequality. These proofs rely on the fact that the subspace of rigid modes is at most one-dimensional, a property which is a consequence of the two-dimensionality of the domain. Numerical results are reported to validate the error estimates. Article in Journal/Newspaper Ice Sheet ORA - Oxford University Research Archive Korn ENVELOPE(159.267,159.267,58.408,58.408) Lagrange ENVELOPE(-62.597,-62.597,-64.529,-64.529) SIAM Journal on Numerical Analysis 61 1 1 25 |
institution |
Open Polar |
collection |
ORA - Oxford University Research Archive |
op_collection_id |
ftuloxford |
language |
English |
description |
Stokes variational inequalities arise in the formulation of glaciological problems involving contact. We consider the problem of a two-dimensional marine ice sheet with a grounding line, although the analysis presented here is extendable to other contact problems in glaciology, such as that of subglacial cavitation. The analysis of this problem and its discretisation is complicated by the nonlinear rheology commonly used for modelling ice, the enforcement of a friction boundary condition given by a power law, and the presence of rigid modes in the velocity space, which render the variational inequality semicoercive. In this work, we consider a mixed formulation of this variational inequality involving a Lagrange multiplier and provide an analysis of its finite element approximation. Error estimates in the presence of rigid modes are obtained by means of a specially-built projection operator onto the subspace of rigid modes and a Korn-type inequality. These proofs rely on the fact that the subspace of rigid modes is at most one-dimensional, a property which is a consequence of the two-dimensionality of the domain. Numerical results are reported to validate the error estimates. |
format |
Article in Journal/Newspaper |
author |
de Diego, G Farrell, P Hewitt, I |
spellingShingle |
de Diego, G Farrell, P Hewitt, I On the finite element approximation of a semicoercive stokes variational inequality arising in glaciology |
author_facet |
de Diego, G Farrell, P Hewitt, I |
author_sort |
de Diego, G |
title |
On the finite element approximation of a semicoercive stokes variational inequality arising in glaciology |
title_short |
On the finite element approximation of a semicoercive stokes variational inequality arising in glaciology |
title_full |
On the finite element approximation of a semicoercive stokes variational inequality arising in glaciology |
title_fullStr |
On the finite element approximation of a semicoercive stokes variational inequality arising in glaciology |
title_full_unstemmed |
On the finite element approximation of a semicoercive stokes variational inequality arising in glaciology |
title_sort |
on the finite element approximation of a semicoercive stokes variational inequality arising in glaciology |
publisher |
Society for Industrial and Applied Mathematics |
publishDate |
2022 |
url |
https://doi.org/10.1137/21M1437640 https://ora.ox.ac.uk/objects/uuid:c607888d-f850-4ca2-99f9-19607bff6435 |
long_lat |
ENVELOPE(159.267,159.267,58.408,58.408) ENVELOPE(-62.597,-62.597,-64.529,-64.529) |
geographic |
Korn Lagrange |
geographic_facet |
Korn Lagrange |
genre |
Ice Sheet |
genre_facet |
Ice Sheet |
op_relation |
doi:10.1137/21M1437640 https://ora.ox.ac.uk/objects/uuid:c607888d-f850-4ca2-99f9-19607bff6435 https://doi.org/10.1137/21M1437640 |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1137/21M1437640 |
container_title |
SIAM Journal on Numerical Analysis |
container_volume |
61 |
container_issue |
1 |
container_start_page |
1 |
op_container_end_page |
25 |
_version_ |
1766031449217040384 |