Wilczyński, F. orcid.org/0000-0002-4560-4444, Davies, C.J. orcid.org/0000-0002-1074-3815 and Jones, C.A. orcid.org/0000-0002-1105-3920 (2023) A two-phase pure slurry model for planetary cores: one-dimensional solutions and implications for Earth's F-layer. Journal of Fluid Mechanics, 976. A5. ISSN 0022-1120
Abstract
We develop and analyse a continuum model of two-phase slurry dynamics for planetary cores. Mixed solid–liquid slurry regions may be ubiquitous in the upper cores of small terrestrial bodies and have also been invoked to explain anomalous seismic structure in the F-layer at the base of Earth’s liquid iron core. These layers are expected to influence the dynamics and evolution of planetary cores, including their capacity to generate global magnetic fields; however, to date, models of two-phase regions in planetary cores have largely ignored the complex fluid dynamics that arises from interactions between phases. As an initial application of our model, and to focus on fundamental fluid dynamical processes, we consider a non-rotating and non-magnetic slurry comprised of a single chemical component with a temperature that is tied to the liquidus. We study one-dimensional solutions in a configuration set up to mimic Earth’s F-layer, varying gravitational strength R, the solid/liquid viscosity ratio λμ and the interaction parameter K, which measures friction between the phases.We develop scalings describing behaviour in the limit R � 1 and λμ � 1, which are in excellent agreement with our numerical results. Application to Earth’s core, where R ∼ 1028 and λμ ∼ 1022, suggests that a pure iron slurry F-layer would contain a mean solid fraction of at most 5 %.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © The Author(s), 2023. Published by Cambridge University Press. This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/ licenses/by/4.0), which permits unrestricted re-use, distribution and reproduction, provided the original article is properly cited. |
Keywords: | multiphase flow; solidification/melting |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Environment (Leeds) > School of Earth and Environment (Leeds) > Inst of Geophysics and Tectonics (IGT) (Leeds) The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Mathematics (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 12 Jan 2024 10:26 |
Last Modified: | 12 Jan 2024 10:26 |
Published Version: | https://www.cambridge.org/core/journals/journal-of... |
Status: | Published |
Publisher: | Cambridge University Press |
Identification Number: | 10.1017/jfm.2023.834 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:207494 |