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On the boundary layer structure of differentially heated cavity flow in a stably stratified porous medium

Published online by Cambridge University Press:  14 August 2007

P. G. DANIELS*
Affiliation:
Centre for Mathematical Science, City University, Northampton Square, London EC1V 0HB, UK

Abstract

This paper considers two-dimensional flow generated in a stably stratified porous medium by monotonic differential heating of the upper surface. For a rectangular cavity with thermally insulated sides and a constant-temperature base, the flow near the upper surface in the high-Darcy–Rayleigh-number limit is shown to consist of a double horizontal boundary layer structure with descending motion confined to the vicinity of the colder sidewall. Here there is a vertical boundary layer structure that terminates at a finite depth on the scale of the outer horizontal layer. Below the horizontal boundary layers the motion consists of a series of weak, uniformly stratified counter-rotating convection cells. Asymptotic results are compared with numerical solutions for the cavity flow at finite values of the Darcy–Rayleigh number.

Type
Papers
Copyright
Copyright © Cambridge University Press 2007

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References

Chang, I. D. & Cheng, P. 1983 Matched asymptotic expansions for free convection about an impermeable horizontal surface in a porous medium. Intl J. Heat Mass Transfer 26, 163173.CrossRefGoogle Scholar
Cheng, P. & Chang, I. D. 1976 On buoyancy induced flows in a saturated porous medium adjacent to impermeable horizontal surfaces. Intl J. Heat Mass Transfer 19, 12671272.Google Scholar
Daniels, P. G. 2006 Shallow cavity flow in a porous medium driven by differential heating. J. Fluid Mech. 565, 441459.CrossRefGoogle Scholar
Daniels, P. G., Blythe, P. A. & Simpkins, P. G. 1982 Thermally driven cavity flows in porous media. Part II. The horizontal boundary-layer structure. Proc. R. Soc. Lond. A 382, 135154.Google Scholar
Daniels, P. G. & Punpocha, M. 2004 Cavity flow in a porous medium driven by differential heating. Intl J. Heat Mass Transfer 47, 30173030.CrossRefGoogle Scholar
Daniels, P. G. & Punpocha, M. 2005 On the boundary-layer structure of cavity flow in a porous medium driven by differential heating. J. Fluid Mech. 532, 321344.CrossRefGoogle Scholar
Tayler, A. B. 1986 Mathematical Models in Applied Mechanics. Clarendon.Google Scholar
Weber, J. E. 1975 The boundary-layer regime for convection in a vertical porous layer. Intl J. Heat Mass Transfer 18, 569573.CrossRefGoogle Scholar