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The collection efficiencies of small droplets falling through a sheared air flow

Published online by Cambridge University Press:  29 March 2006

P. R. Jonas  and
P. Goldsmith
P. R. Jonas
Affiliation:
Cloud Physics Laboratory, Meteorological Office, Bracknell
P. Goldsmith
Affiliation:
Cloud Physics Laboratory, Meteorological Office, Bracknell
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Abstract

Experiments in which collection efficiencies have been measured for small droplets falling through a sheared air flow are described. The results indicate that these collection efficiencies are much greater than for the same droplets falling in still air when the collecting droplets are less than about 25μm in radius, but that for larger droplets there is very little effect. Calculations of the collision efficiencies of rigid spheres moving in a sheared air flow are presented but these fail to account for the experimental results. These discrepancies are discussed.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 52 , Issue 3 , 11 April 1972 , pp. 593 - 608
Copyright
© 1972 Cambridge University Press

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