Turbulent rotating rayleigh-benard convection

Spatiotemporal and statistical study

A. Husain, M. F. Baig, H. Varshney

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

The present study involves a 3D numerical investigation of rotating Rayleigh-Benard convection in a large aspect-ratio (8:8:1) rectangular enclosure. The rectangular cavity is rotated about a vertical axis passing through the center of the cavity. The governing equations of mass, momentum, and energy for a frame rotating with the enclosure, subject to generalized Boussinesq approximation applied to the body and centrifugal force terms, have been solved on a collocated grid using a semi-implicit finite difference technique. The simulations have been carried out for liquid metal flows having a fixed Prandtl number Pr=0.01 and fixed Rayleigh number Ra=107 while rotational Rayleigh number Raw and Taylor number Ta are varied through nondimensional rotation rate (ω) ranging from 0 to 104. Generation of large-scale structures is observed at low-rotation (ω=10) rates though at higher-rotation rates (ω=104) the increase in magnitude of Coriolis forces leads to redistribution of buoyancy-induced vertical kinetic energy to horizontal kinetic energy. This brings about inhibition of vertical fluid transport, thereby leading to reduced vertical heat transfer. The magnitude of rms velocities remains unaffected with an increase in Coriolis forces from ω=0 to 104. An increase in rotational buoyancy (Raw), at constant rotation rate (ω=104), on variation in Raw/Ta from 10-3 to 10-2 results in enhanced breakup of large-scale structures with a consequent decrease in rms velocities but with negligible reduction in vertical heat transport.

Original languageEnglish
Pages (from-to)1-10
Number of pages10
JournalJournal of Heat Transfer
Volume131
Issue number2
DOIs
Publication statusPublished - Feb 2009

Fingerprint

Rayleigh-Benard convection
Coriolis force
Buoyancy
Enclosures
Kinetic energy
Rayleigh number
enclosure
buoyancy
Prandtl number
kinetic energy
Liquid metals
Boussinesq approximation
Aspect ratio
Momentum
cavities
centrifugal force
liquid metals
Heat transfer
Fluids
Convection

Keywords

  • Coriolis forces
  • Low-Prandtl fluid
  • Rotating convection
  • Rotational buoyancy
  • Statistical properties

ASJC Scopus subject areas

  • Mechanical Engineering
  • Mechanics of Materials
  • Materials Science(all)
  • Condensed Matter Physics

Cite this

Turbulent rotating rayleigh-benard convection : Spatiotemporal and statistical study. / Husain, A.; Baig, M. F.; Varshney, H.

In: Journal of Heat Transfer, Vol. 131, No. 2, 02.2009, p. 1-10.

Research output: Contribution to journalArticle

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