Turbulent rotating convection at high Rayleigh and Taylor numbers

J. J. Niemela, S. Babuin, K. R. Sreenivasan

Research output: Contribution to journalArticle

Abstract

We report heat transport measurements in a cylindrical convection apparatus rotating about the vertical axis. The aspect ratio was 1/2. The working fluid was cryogenic helium gas and the following parameter ranges applied: the Rayleigh number, Ra, varied in the range 1011 < Ra < 4.3 1015, the Taylor number, Ta, varied in the range 1011 < Ta < 3 1015, the convective Rossby number, Ro, varied in the range 0.4 < Ro < 1.6 and the Prandtl number, Pr, varied in the range 0.7 < Pr < 5.9. Boussinesq conditions applied quite closely. The heat transport for steady rotation, under all conditions of the present experiments, was smaller than that for the non-rotating case. When the rotation rate varied periodically in time, a sharp transition to a state of significantly enhanced heat transport was observed for modulation Taylor numbers Ta *<1014, where Ta* is based on the peak value of the modulation angular velocity.

Original languageEnglish (US)
Pages (from-to)509-522
Number of pages14
JournalJournal of Fluid Mechanics
Volume649
DOIs
StatePublished - Apr 25 2010

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Rayleigh number
convection
heat
Modulation
modulation
working fluids
Prandtl number
Angular velocity
angular velocity
Cryogenics
cryogenics
Helium
aspect ratio
Aspect ratio
helium
Fluids
Gases
gases
Hot Temperature
Convection

ASJC Scopus subject areas

  • Mechanical Engineering
  • Mechanics of Materials
  • Condensed Matter Physics

Cite this

Turbulent rotating convection at high Rayleigh and Taylor numbers. / Niemela, J. J.; Babuin, S.; Sreenivasan, K. R.

In: Journal of Fluid Mechanics, Vol. 649, 25.04.2010, p. 509-522.

Research output: Contribution to journalArticle

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