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Close spacing of settling chamber screens

Published online by Cambridge University Press:  04 July 2016

P. E. Hancock  and
A. E. Johnson
P. E. Hancock
Affiliation:
Department of Mechanical Engineering, University of Surrey, Guildford, UK
A. E. Johnson*
Affiliation:
Department of Mechanical Engineering, University of Surrey, Guildford, UK
*
†Now at BP Research, Sunbury-on-Thames, Middlesex, UK.
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Extract

Screen separations as little as 0.02 chamber diameters do not adversely affect suppression of mean-flow non-uniformity provided the overall pressure drop coefficient, K, does not exceed about 3.5. At larger K a velocity overshoot develops near the wall boundary layers, which decreases only slowly with wider separation. A simple approximate extension can be made to the theory of Taylor and Batchelor for any number of closely-spaced screens. This shows good agreement with measurements and with low-drag screens predicts perfect attenuation when the overall pressure-drop coefficient is 3.2 or 7.6. Some inferences regarding the effect of close screens on turbulence suppression are also drawn.

Type
Research Article
Information
The Aeronautical Journal , Volume 101 , Issue 1004 , April 1997 , pp. 179 - 183
Copyright
Copyright © Royal Aeronautical Society 1997 

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