Currie, L, Barker, A orcid.org/0000-0003-4397-7332, Lithwick, Y et al. (1 more author) (2020) Convection with Misaligned Gravity and Rotation: Simulations and Rotating Mixing Length Theory. Monthly Notices of the Royal Astronomical Society. ISSN 0035-8711
Abstract
We present numerical simulations, using two complementary setups, of rotating Boussinesq thermal convection in a three-dimensional Cartesian geometry with misaligned gravity and rotation vectors. This model represents a small region at a non-polar latitude in the convection zone of a star or planet. We investigate the effects of rotation on the bulk properties of convection at different latitudes, focusing on determining the relation between the heat flux and temperature gradient. We show that our results may be interpreted using rotating mixing length theory (RMLT). The simplest version of RMLT (due to Stevenson) considers the single mode that transports the most heat. This works reasonably well in explaining our results, but there is a systematic departure from these predictions (up to approximately 30% in the temperature gradient) at mid-latitudes. We develop a more detailed treatment of RMLT that includes the transport afforded by multiple modes, and we show that this accounts for most of the systematic differences. We also show that convectively-generated zonal flows and meridional circulations are produced in our simulations, and that their properties depend strongly on the dimensions of the box. These flows also affect the heat transport, contributing to departures from RMLT at some latitudes. However, we find the theoretical predictions of the multi-mode theory for the mid-layer temperature gradient, the root-mean-square (RMS) vertical velocity, the RMS temperature fluctuation, and the spatial spectrum of the heat transport at different latitudes, are all in reasonably good agreement with our numerical results when zonal flows are small.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | This article is protected by copyright. This is an author produced version of a paper accepted for publication in Monthly Notices of the Royal Astronomical Society. Uploaded in accordance with the publisher's self-archiving policy. |
Keywords: | Convection, hydrodynamics, stars: interiors, stars: rotation, Sun: interior, planets and satellites: interiors |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Mathematics (Leeds) > Applied Mathematics (Leeds) |
Funding Information: | Funder Grant number Leverhulme Trust ECF-2014-216 Science & Technology Facilities Council (STFC) ST/R00059X/1 Science & Technology Facilities Council (STFC) ST/S000275/1 |
Depositing User: | Symplectic Publications |
Date Deposited: | 11 Feb 2020 12:37 |
Last Modified: | 11 Feb 2020 12:46 |
Status: | Published online |
Publisher: | Oxford University Press |
Identification Number: | 10.1093/mnras/staa372 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:156750 |