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Natural convection above unconfined horizontal surfaces

Published online by Cambridge University Press:  29 March 2006

Zeev Rotem  and
Lutz Claassen
Zeev Rotem
Affiliation:
Department of Mechanical Engineering, University of British Columbia, Vancouver 8, B.C. Canada
Lutz Claassen
Affiliation:
Department of Mechanical Engineering, University of British Columbia, Vancouver 8, B.C. Canada
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Abstract

The paper discusses free convective flows above a horizontal plate, both theoretically and on the basis of experiments which yield quantitative data. The theory is applicable to the semi-infinite plate and is extended to cover the complete range of Prandtl number values including Pr → 0 and Pr → ∞. Experiments were carried out to demonstrate the existence of a laminar boundary layer above a horizontal plate at intermediate Grashof (respectively Rayleigh) numbers, and its extent along the plate. This layer breaks down into large-eddy instability some distance from the leading edge. The value of the critical Rayleigh number for this to occur, obtained experimentally using semi-focusing colour-Schlieren photography is in reasonable qualitative agreement with previously known data (Tritton 1963a,b).

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 39 , Issue 1 , 23 October 1969 , pp. 173 - 192
Copyright
© 1969 Cambridge University Press

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References

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