Horizontal convection: shallow enclosures confine heating and cooling near sidewalls

Sajjad Hossain, Tony Vo, Gregory J. Sheard

Research output: Chapter in Book/Report/Conference proceedingConference PaperOther

Abstract

Horizontal convection is investigated numerically in shallow rectangular enclosures with height-to-length aspect ratios up to 160 times shallower than that has been studied previously to determine the effect of ocean-relevant aspect ratio confinement on horizontal convection. Simulations are conducted at a Prandtl number of Pr = 6.14 (consistent with water) across a wide span of Rayleigh numbers, (10 ≤ Ra ≤ 1016) and aspect ratios (10-3 ≤ A ≤ 0.16). A critical Ra is found marking the transition between the diffusion-dominated and convective regimes across these small aspect ratios. The heat transfer scalings governing these regimes are determined as a function of aspect ratio. The critical Nu and Ra are found to closely fit power-law scalings Ra ∝ A-4 and Nu ∝ Ra-1/4. These scalings lead to modified Nu and Ra parameters found to control the flow at lower Rayleigh numbers, which provide evidence that at lower Ra, the height of the enclosure controls the flow dynamics. Furthermore, a previously unseen behaviour is discovered whereby decreasing aspect ratio of the enclosure, the formation of an increasingly large horizontally uniform zone is evident, which implies that the heating and cooling increasingly confined to regions close to the end-walls.

Original languageEnglish
Title of host publicationProceedings of the 21st Australasian Fluid Mechanics Conference, AFMC 2018
EditorsTimothy C.W. Lau, Richard M. Kelso
PublisherAustralasian Fluid Mechanics Society
ISBN (Electronic)9780646597843
Publication statusPublished - 2018
EventAustralasian Fluid Mechanics Conference 2018 - Adelaide Convention Centre, Adelaide, Australia
Duration: 10 Dec 201813 Dec 2018
Conference number: 21st
https://aomevents.eventsair.com/QuickEventWebsitePortal/21st-australasian-fluid-mechanics-conference/afmc2018

Publication series

NameProceedings of the 21st Australasian Fluid Mechanics Conference, AFMC 2018

Conference

ConferenceAustralasian Fluid Mechanics Conference 2018
Abbreviated titleAFMC 2018
CountryAustralia
CityAdelaide
Period10/12/1813/12/18
Internet address

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