Dynamic recrystallization during deformation of polycrystalline ice: insights from numerical simulations
The flow of glaciers and polar ice sheets is controlled by the highly anisotropic rheology of ice crystals that have hexagonal symmetry (ice lh). To improve our knowledge of ice sheet dynamics, it is necessary to understand how dynamic recrystallization (DRX) controls ice microstructures and rheolog...
Published in: | Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences |
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Online Access: | https://epic.awi.de/id/eprint/42979/ https://epic.awi.de/id/eprint/42979/1/Llorens2017.pdf https://doi.org/10.1098/rsta.2015.0346 https://hdl.handle.net/10013/epic.49523 https://hdl.handle.net/10013/epic.49523.d001 |
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ftawi:oai:epic.awi.de:42979 2024-09-15T18:12:29+00:00 Dynamic recrystallization during deformation of polycrystalline ice: insights from numerical simulations Llorens, Maria-Gema Griera, Albert Steinbach, Florian Bons, Paul D. Gomez-Rivas, Enrique Jansen, Daniela Roessiger, Jens Lebensohn, Ricardo A. Weikusat, Ilka 2017 application/pdf https://epic.awi.de/id/eprint/42979/ https://epic.awi.de/id/eprint/42979/1/Llorens2017.pdf https://doi.org/10.1098/rsta.2015.0346 https://hdl.handle.net/10013/epic.49523 https://hdl.handle.net/10013/epic.49523.d001 unknown The Royal Society Publishing https://epic.awi.de/id/eprint/42979/1/Llorens2017.pdf https://hdl.handle.net/10013/epic.49523.d001 Llorens, M. G. , Griera, A. , Steinbach, F. , Bons, P. D. , Gomez-Rivas, E. , Jansen, D. orcid:0000-0002-4412-5820 , Roessiger, J. , Lebensohn, R. A. and Weikusat, I. orcid:0000-0002-3023-6036 (2017) Dynamic recrystallization during deformation of polycrystalline ice: insights from numerical simulations , Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 375 (2086), p. 20150346 . doi:10.1098/rsta.2015.0346 <https://doi.org/10.1098/rsta.2015.0346> , hdl:10013/epic.49523 EPIC3Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, The Royal Society Publishing, 375(2086), pp. 20150346, ISSN: 1364-503X Article isiRev 2017 ftawi https://doi.org/10.1098/rsta.2015.0346 2024-06-24T04:16:35Z The flow of glaciers and polar ice sheets is controlled by the highly anisotropic rheology of ice crystals that have hexagonal symmetry (ice lh). To improve our knowledge of ice sheet dynamics, it is necessary to understand how dynamic recrystallization (DRX) controls ice microstructures and rheology at different boundary conditions that range from pure shear flattening at the top to simple shear near the base of the sheets. We present a series of two-dimensional numerical simulations that couple ice deformation with DRX of various intensities, paying special attention to the effect of boundary conditions. The simulations show how similar orientations of c-axis maxima with respect to the finite deformation direction develop regardless of the amount of DRX and applied boundary conditions. In pure shear this direction is parallel to the maximum compressional stress, while it rotates towards the shear direction in simple shear. This leads to strain hardening and increased activity of non-basal slip systems in pure shear and to strain softening in simple shear. Therefore, it is expected that ice is effectively weaker in the lower parts of the ice sheets than in the upper parts. Strain-rate localization occurs in all simulations, especially in simple shear cases. Recrystallization suppresses localization, which necessitates the activation of hard, non-basal slip systems.This article is part of the themed issue {\textquoteleft}Microdynamics of ice{\textquoteright}. Article in Journal/Newspaper Ice Sheet Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 375 2086 20150346 |
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Open Polar |
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Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
op_collection_id |
ftawi |
language |
unknown |
description |
The flow of glaciers and polar ice sheets is controlled by the highly anisotropic rheology of ice crystals that have hexagonal symmetry (ice lh). To improve our knowledge of ice sheet dynamics, it is necessary to understand how dynamic recrystallization (DRX) controls ice microstructures and rheology at different boundary conditions that range from pure shear flattening at the top to simple shear near the base of the sheets. We present a series of two-dimensional numerical simulations that couple ice deformation with DRX of various intensities, paying special attention to the effect of boundary conditions. The simulations show how similar orientations of c-axis maxima with respect to the finite deformation direction develop regardless of the amount of DRX and applied boundary conditions. In pure shear this direction is parallel to the maximum compressional stress, while it rotates towards the shear direction in simple shear. This leads to strain hardening and increased activity of non-basal slip systems in pure shear and to strain softening in simple shear. Therefore, it is expected that ice is effectively weaker in the lower parts of the ice sheets than in the upper parts. Strain-rate localization occurs in all simulations, especially in simple shear cases. Recrystallization suppresses localization, which necessitates the activation of hard, non-basal slip systems.This article is part of the themed issue {\textquoteleft}Microdynamics of ice{\textquoteright}. |
format |
Article in Journal/Newspaper |
author |
Llorens, Maria-Gema Griera, Albert Steinbach, Florian Bons, Paul D. Gomez-Rivas, Enrique Jansen, Daniela Roessiger, Jens Lebensohn, Ricardo A. Weikusat, Ilka |
spellingShingle |
Llorens, Maria-Gema Griera, Albert Steinbach, Florian Bons, Paul D. Gomez-Rivas, Enrique Jansen, Daniela Roessiger, Jens Lebensohn, Ricardo A. Weikusat, Ilka Dynamic recrystallization during deformation of polycrystalline ice: insights from numerical simulations |
author_facet |
Llorens, Maria-Gema Griera, Albert Steinbach, Florian Bons, Paul D. Gomez-Rivas, Enrique Jansen, Daniela Roessiger, Jens Lebensohn, Ricardo A. Weikusat, Ilka |
author_sort |
Llorens, Maria-Gema |
title |
Dynamic recrystallization during deformation of polycrystalline ice: insights from numerical simulations |
title_short |
Dynamic recrystallization during deformation of polycrystalline ice: insights from numerical simulations |
title_full |
Dynamic recrystallization during deformation of polycrystalline ice: insights from numerical simulations |
title_fullStr |
Dynamic recrystallization during deformation of polycrystalline ice: insights from numerical simulations |
title_full_unstemmed |
Dynamic recrystallization during deformation of polycrystalline ice: insights from numerical simulations |
title_sort |
dynamic recrystallization during deformation of polycrystalline ice: insights from numerical simulations |
publisher |
The Royal Society Publishing |
publishDate |
2017 |
url |
https://epic.awi.de/id/eprint/42979/ https://epic.awi.de/id/eprint/42979/1/Llorens2017.pdf https://doi.org/10.1098/rsta.2015.0346 https://hdl.handle.net/10013/epic.49523 https://hdl.handle.net/10013/epic.49523.d001 |
genre |
Ice Sheet |
genre_facet |
Ice Sheet |
op_source |
EPIC3Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, The Royal Society Publishing, 375(2086), pp. 20150346, ISSN: 1364-503X |
op_relation |
https://epic.awi.de/id/eprint/42979/1/Llorens2017.pdf https://hdl.handle.net/10013/epic.49523.d001 Llorens, M. G. , Griera, A. , Steinbach, F. , Bons, P. D. , Gomez-Rivas, E. , Jansen, D. orcid:0000-0002-4412-5820 , Roessiger, J. , Lebensohn, R. A. and Weikusat, I. orcid:0000-0002-3023-6036 (2017) Dynamic recrystallization during deformation of polycrystalline ice: insights from numerical simulations , Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 375 (2086), p. 20150346 . doi:10.1098/rsta.2015.0346 <https://doi.org/10.1098/rsta.2015.0346> , hdl:10013/epic.49523 |
op_doi |
https://doi.org/10.1098/rsta.2015.0346 |
container_title |
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences |
container_volume |
375 |
container_issue |
2086 |
container_start_page |
20150346 |
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1810450069051146240 |