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Time similarity analysis of unsteady buoyant plumes in neutral surroundings

Published online by Cambridge University Press:  19 April 2006

M. A. Delichatsios
M. A. Delichatsios
Affiliation:
Factory Mutual Research, 1151 Boston-Providence Turnpike, Norwood, Massachusetts 02062
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Abstract

A time similarity formulation of the flow equations for unsteady plumes is shown to exist only when the buoyancy flux at the source varies as a power function of time. The time similarity equations for unsteady plumes are solved numerically. It is shown that the velocity of the leading edge of the plume is less (at most the 0·42 fraction) than the velocity inside the plume behind its leading edge; this observation is consistent with Turner's (1962) results on the behaviour of a starting plume with constant buoyancy flux at the source. Finally, experimental results of axial temperature histories in the buoyant plume generated by a fast-growing fire are compared with the theoretical predictions.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 93 , Issue 2 , 26 July 1979 , pp. 241 - 250
Copyright
© 1979 Cambridge University Press

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References

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