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On the effect of distributed cooling in natural ventilation

Published online by Cambridge University Press:  26 March 2008

S. R. LIVERMORE  and
A. W. WOODS
S. R. LIVERMORE
Affiliation:
BP Institute for Multiphase flow, University of Cambridge, Cambridge, CB3 0EZ, UK
A. W. WOODS
Affiliation:
BP Institute for Multiphase flow, University of Cambridge, Cambridge, CB3 0EZ, UK
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Abstract

We examine the natural ventilation flows which develop when a low-level heat source interacts with a distributed zone of cooling at high level in an enclosed space. We develop some new analogue laboratory experiments in which we use a saline plume to model a localized heat source and a heated plate to model a distributed source of cooling. The experiments show that in a building with a low-level point source of heating, a two-layer steady stratification develops in which the depth of the lower layer decreases as the intensity of the cooling at the ceiling increases. We develop a theoretical model which accounts for the penetrative entrainment across the interface associated with the convection in the upper layer. We show that this becomes more dominant as the cooling increases and eventually the room becomes well-mixed. We discuss the role of such distributed cooling on the design of natural ventilation and its ability to provide sufficient flow and adequate temperature control.

Type
Papers
Information
Journal of Fluid Mechanics , Volume 600 , 10 April 2008 , pp. 1 - 17
Copyright
Copyright © Cambridge University Press 2008

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References

REFERENCES

Baines, W. D. 1975 Entrainment by a plume or jet at a density interface. J. Fluid Mech. 68, 309–320.Google Scholar
Baines, W. D. 1983 A technique for the measurement of volume flux in a plume. J. Fluid Mech. 132, 247–256.Google Scholar
Cardoso, S. S. S. & Woods, A. W. 1996 Interfacial turbulent mixing in stratified magma reservoir. J. Volcanolo. Geotherm. Res. 73, 157–175.Google Scholar
CIBSE 1999 Environmental Design. CIBSE Guide A, London.Google Scholar
Davies, M. G. 2004 Building Heat Transfer. Wiley.Google Scholar
Deardorff, J. W., Willis, G. E. & Lilly, D. K. 1969 Laboratory investigation of non-steady penetrative convection. J. Fluid Mech. 35, 7–31.Google Scholar
Denton, R. A. & Wood, I. R. 1981 Penetrative convection at low peclet number. J. Fluid Mech. 111, 1–21.CrossRefGoogle Scholar
Fisk, D. J. 1981 Thermal Control of Buildings. Applied Science.Google Scholar
Gladstone, C. & Woods, A. W. 2001 On buoyancy-driven natural ventilation of a room with a heated floor. J. Fluid Mech. 441, 293–314.Google Scholar
Holford, J. & Woods, A. W. 2007 The role of thermal mass in natural ventilation. J. Fluid Mech. 580, 3–29.Google Scholar
Li, Y. & Yam, J. C. W. 2004 Designing thermal mass in naturally ventilated buildings. Intl J. Ventilation 2, 313–324.CrossRefGoogle Scholar
Linden, P. F. 1999 The fluid mechanics of natural ventilation. Annu. Rev. Fluid Mech. 31, 201–238.Google Scholar
Linden, P. F., Lane-Serff, G. F. & Smeed, D. A. 1990 Emptying filling boxes: the fluid mechanics of natural ventilation. J. Fluid Mech. 212, 300–335.Google Scholar
Lister, J. A. 1995 On penetrative convection at low peclet number. J. Fluid Mech. 292, 229–248.CrossRefGoogle Scholar
McDougall, T. J. 1983 Double-diffusive plumes in unconfined and confined environments. J. Fluid Mech. 133, 321–343.CrossRefGoogle Scholar
Morton, B. R., Taylor, G. I. & Turner, J. S. 1956 Turbulent gravitional convection from maintained and instantaneous sources. Proc. R. Soci. Lond A 234, 1–23.Google Scholar
Novoselac, A. & Srebric, J. 2002 A critical review on the performance and design of combined cooled ceiling and displacement ventilation systems. Energy and Buildings 34, 497–509.Google Scholar
Sandberg, M. & Lindstrom, S. 1990 Stratified flow in ventilated rooms- a model study. Proc. RoomVent Conference, Oslo, Norway.Google Scholar
Turner, J. S. 1979 Buoyancy Effects in Fluids. Cambridge University Press.Google Scholar
Woods, A. W., Caulfield, C. P. & Phillips, J. C. 2003 Blocked natural ventilation: the effect of a source mass flux. J. Fluid Mech. 495, 119–133.Google Scholar
Zilitinkevich, S. S. 1991 Turbulent penetrative convection. Avebury Tech. pp. 1–77.Google Scholar