Poster Open Access

# Convective turbulent viscosity acting on equilibrium tidal flows: new frequency scaling of the effective viscosity

Craig Duguid; Adrian J Barker; C A Jones

### DataCite XML Export

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<identifier identifierType="DOI">10.5281/zenodo.4562742</identifier>
<creators>
<creator>
<creatorName>Craig Duguid</creatorName>
<nameIdentifier nameIdentifierScheme="ORCID" schemeURI="http://orcid.org/">0000-0003-1199-3469</nameIdentifier>
<affiliation>Newcastle University</affiliation>
</creator>
<creator>
<nameIdentifier nameIdentifierScheme="ORCID" schemeURI="http://orcid.org/">0000-0003-4397-7332</nameIdentifier>
<affiliation>University of Leeds</affiliation>
</creator>
<creator>
<creatorName>C A Jones</creatorName>
<affiliation>University of Leeds</affiliation>
</creator>
</creators>
<titles>
<title>Convective turbulent viscosity acting on equilibrium tidal flows: new frequency scaling of the effective viscosity</title>
</titles>
<publisher>Zenodo</publisher>
<publicationYear>2021</publicationYear>
<subjects>
<subject>Tidal interactions</subject>
</subjects>
<contributors>
<contributor contributorType="ContactPerson">
<contributorName>Craig Duguid</contributorName>
<nameIdentifier nameIdentifierScheme="ORCID" schemeURI="http://orcid.org/">0000-0003-1199-3469</nameIdentifier>
<affiliation>Newcastle University</affiliation>
</contributor>
<contributor contributorType="Supervisor">
<nameIdentifier nameIdentifierScheme="ORCID" schemeURI="http://orcid.org/">0000-0003-4397-7332</nameIdentifier>
<affiliation>University of Leeds</affiliation>
</contributor>
<contributor contributorType="Supervisor">
<contributorName>C A Jones</contributorName>
<affiliation>University of Leeds</affiliation>
</contributor>
</contributors>
<dates>
<date dateType="Issued">2021-02-25</date>
</dates>
<resourceType resourceTypeGeneral="Text">Poster</resourceType>
<alternateIdentifiers>
<alternateIdentifier alternateIdentifierType="url">https://zenodo.org/record/4562742</alternateIdentifier>
</alternateIdentifiers>
<relatedIdentifiers>
<relatedIdentifier relatedIdentifierType="DOI" relationType="Cites" resourceTypeGeneral="JournalArticle">10.1093/mnras/staa2216</relatedIdentifier>
<relatedIdentifier relatedIdentifierType="DOI" relationType="Cites" resourceTypeGeneral="JournalArticle">10.1093/mnras/stz2899</relatedIdentifier>
<relatedIdentifier relatedIdentifierType="DOI" relationType="IsVersionOf">10.5281/zenodo.4562741</relatedIdentifier>
<relatedIdentifier relatedIdentifierType="URL" relationType="IsPartOf">https://zenodo.org/communities/coolstars20half</relatedIdentifier>
</relatedIdentifiers>
<rightsList>
<rights rightsURI="info:eu-repo/semantics/openAccess">Open Access</rights>
</rightsList>
<descriptions>
<description descriptionType="Abstract">&lt;p&gt;Tidal interactions are important in driving spin and orbital evolution in various astrophysical systems such as hot Jupiters, close binary stars and planetary satellites. However, the fluid dynamical mechanisms responsible for tidal dissipation in giant planets and stars remain poorly understood. One key mechanism is the interaction between tidal flows and turbulent convection which is thought to act as an eddy viscosity (&lt;span class="math-tex"&gt;$$\nu_E$$&lt;/span&gt;) dampening the large scale tidal flow. The efficiency of this mechanism has long been debated, particularly in the regime of fast tides, when the tidal frequency (&lt;span class="math-tex"&gt;$$\omega$$&lt;/span&gt;) exceeds the turnover frequency of the dominant convective eddies (&lt;span class="math-tex"&gt;$$\omega_c$$&lt;/span&gt;). The pioneering work of Zahn (1966) proposed that &amp;nbsp;while Goldreich &amp;amp; Nicholson (1977) found .&lt;/p&gt;

&lt;p&gt;&amp;nbsp;&lt;/p&gt;

&lt;p&gt;Using hydrodynamical simulations we investigate the dissipation of the large scale (non-wavelike) equilibrium tide as a result of its interaction with convection. Our approach is to conduct a wide parameter survey in order to study the interaction between an oscillatory background shear flow, which represents a large-scale tidal flow, and the convecting fluid inside a small patch of a star or planet. We simulate Rayleigh-B&amp;eacute;nard convection in this Cartesian model and explore how the effective viscosity of the turbulence depends on the tidal (shear) frequency.&lt;/p&gt;

&lt;p&gt;&amp;nbsp;&lt;/p&gt;

&lt;p&gt;We will present the results from our simulations to determine the effective viscosity, and its dependence on the tidal frequency in both laminar and weakly turbulent regimes. The main result is a new scaling law for the frequency dependence of the effective viscosity which has not previously been observed in simulations or predicted by theory and occurs for shear frequencies smaller than those in the fast tides regime. These results have important implications for tidal dissipation in convection zones of stars and planets, and indicate that the classical tidal theory of the equilibrium tide in stars and giant planets should be revisited.&lt;/p&gt;</description>
<description descriptionType="Other">{"references": ["Zahn J. P., 1966, \"Les mar\u00e9es dans une \u00e9toile double serr\u00e9e\", Annales d'Astrophysique, 29, 313", "Goldreich P., Nicholson P. D., 1977, \"Turbulent viscosity and Jupiter's tidal Q\", Icarus, 30, 301, DOI: 10.1016/0019-1035(77)90163-4", "Ogilvie G. I., Lesur G., 2012, \"On the interaction between tides and convection: Tides and convection\", Monthly Notices of the Royal Astronomical Society, 422, 1975, DOI: 10.1111/j.1365-2966.2012.20630.x", "Maciejewski G., et al., 2018, \"Planet-star interactions with precise transit timing. I. The rened orbital decay rate forWASP-12 b and initial constraints for HAT-P-23 b, KELT-1 b, KELT-16 b, WASP-33 b and WASP-103 b\", Acta Astronomica, 68, 371, DOI: 10.32023/0001-5237/68.4.4", "Duguid C. D., Barker A. J., Jones C. A., 2020, \"Tidal  flows with convection: frequency dependence of the effective viscosity and evidence for anti-dissipation\", Monthly Notices of the Royal Astronomical Society, 491, 923, DOI: 10.1093/mnras/stz2899", "Duguid C. D., Barker A. J., Jones C. A., 2020, \"Convective turbulent viscosity acting on equilibrium tidal  flows: new frequency scaling of the effective viscosity\", Monthly Notices of the Royal Astronomical Society, 497, 3400, DOI: 10.1093/mnras/staa2216"]}</description>
</descriptions>
</resource>

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