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Investigation of turbulent thermal convection between horizontal plates

Published online by Cambridge University Press:  28 March 2006

J. W. Deardorff
Affiliation:
National Center for Atmospheric Research, Boulder, Colorado
G. E. Willis
Affiliation:
National Center for Atmospheric Research, Boulder, Colorado

Abstract

Properties of turbulent thermal convection were measured in air between horizontal plates maintained at constant temperatures. Rayleigh numbers of 6·3 × 105, 2·5 × 106 and 1·0 × 107 were studied with a convection chamber designed to allow measurements to be taken along a horizontal path. Vertical profiles are presented of horizontally averaged temperature; r.m.s. fluctuations of temperature, horizontal velocity and vertical velocity; total heat flux; the correlation coefficient between vertical velocity and temperature; all terms in the thermal variance equation; and of terms in the turbulent kinetic energy balance.

One-dimensional spectra of temperature, horizontal velocity and vertical velocity at two different heights all disclose large intensity for waves of length 5 to 15 times the plate separation. Secondary peaks occur for scales of from 0·7 to 1·7 times the separation height.

Many of the observations are consistent with a thermal structure dominated by plumes extending most or all of the distance between plates.

Type
Research Article
Copyright
© 1967 Cambridge University Press

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References

Collis, D. C. & Williams, M. J. 1959 Two-dimensional convection from heated wires at low Reynolds numbers J. Fluid Mech. 6, 357384.Google Scholar
Deardorff, J. W. 1964 A numerical study of two-dimensional parallel-plate convection J. Atmos. Sci. 21, 419438.Google Scholar
Deardorff, J. W. 1965 A numerical study of paeudo three-dimensional parallel-plate convection J. Atmos. Sci. 22, 419435.Google Scholar
Deardorff, J. W. & Willis, G. E. 1965 The effect of two-dimensionality on the suppression of thermal turbulence J. Fluid Mech. 23, 337353.Google Scholar
Deardorff, J. W. & Willis, G. E. 1967 The free-convection temperature profile. Quart. J. Roy. Meteor. Soc. 93 (to be published).Google Scholar
Globe, S. & Dropkin, D. 1959 Natural convection heat transfer in liquids confined by two horizontal plates and heated from below. 1958 Heat Trans. & Fluid Mech. Inst. pp. 156165. Berkeley, University of California.
Hinze, J. O. 1959 Turbulence. New York: New York.
King, L. V. 1914 On the convection of heat from small cylinders in a stream of fluid. Determination of convection constants of small platinum wires with application to hot-wire anemometry. Phil. Trans A 214, 373432.Google Scholar
Malkus, W. V. R. 1954a Discrete transitions in turbulent convection. Proc. Roy. Soc A 225, 185195.Google Scholar
Malkus, W. V. R. 1954b The heat transport and spectrum of thermal turbulence. Proc. Roy. Soc A 225, 196212.Google Scholar
Silveston, P. L. 1958 Wärmedurchgang in Waagerechte Flüssigkeitsschlichten Forsch. Ing. Wes. 24, 5969.Google Scholar
Somerscales, E. F. C. 1965 Experimental investigation of the temperature distribution in a horizontal fluid layer heated from below. Ph.D. Dissertation, Cornell University, Dept. Mech. Eng., available from University Microfilms Inc., Ann Arbor, Michigan.
Thomas, D. B. & Townsend, A. A. 1957 Turbulent convection over a heated horizontal surface J. Fluid Mech. 2, 473492.Google Scholar