Heat convection in a vertical channel : Plumes versus turbulent diffusion

Mathieu Gibert 1 Hervé Pabiou 1 Jean-Christophe Tisserand 1 Betina Gertjerenken 1 Bernard Castaing 1 Francesca Chillà 1
1 Phys-ENS - Laboratoire de Physique de l'ENS Lyon
Abstract : Following a previous study [Gibert , Phys. Rev. Lett. 96, 084501 (2006)], convective heat transfer in a vertical channel of moderate dimensions follows purely inertial laws. It would be therefore a good model for convective flows of stars and ocean. Here we report new measurements on this system. We use an intrinsic length in the definition of the characteristic Rayleigh and Reynolds numbers. We explicit the relation between this intrinsic length and the thermal correlation length. Using particle imaging velocimetry, we show that the flow undergoes irregular reversals. We measure the average velocity profiles and the Reynolds stress tensor components. The momentum flux toward the vertical walls seems negligible compared to the shear turbulent stress. A mixing length theory seems adequate to describe the horizontal turbulent heat and momentum fluxes, but fails for the vertical ones. We propose a naive model for vertical heat transport inspired by the Knudsen regime in gases.
Keywords : Particle image velocimetry Rayleigh Benard Convection Thermal plumes Turbulent diffusion Turbulent thermal convection
Document type :
Journal articles
Complete list of metadatas

Cited literature [16 references]  Display  Hide  Download
https://hal-ens-lyon.archives-ouvertes.fr/ensl-00377244
Contributor : Mathieu Gibert <>
Submitted on : Tuesday, April 21, 2009 - 4:27:33 PM
Last modification on : Thursday, November 21, 2019 - 2:34:59 AM
Long-term archiving on: Thursday, June 10, 2010 - 9:17:57 PM

File

Physics_of_Fluids_2009_Gibert_...
Files produced by the author(s)

Identifiers

Collections

CNRS | ENS-LYON | UNIV-LYON1 | UDL

Citation

Mathieu Gibert, Hervé Pabiou, Jean-Christophe Tisserand, Betina Gertjerenken, Bernard Castaing, et al.. Heat convection in a vertical channel : Plumes versus turbulent diffusion. Physics of Fluids, American Institute of Physics, 2009, 21 (3), pp.035109. ⟨10.1063/1.3085812⟩. ⟨ensl-00377244⟩

Export

BibTeX TEI DC DCterms EndNote

Share

Metrics

Record views

254

Files downloads

440

Contact

Informations

CCSD