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The effects of turbulence and surface roughness on the drag of spheres in thin jets

Published online by Cambridge University Press:  04 July 2016

R. S. Neve
Affiliation:
Department of Mechanical EngineeringCity University, London
F. B. Jaafar
Affiliation:
Department of Mechanical EngineeringCity University, London

Abstract

An extension is made to previous work on spheres in thin jets to cover the cases of high stream turbulence and sphere surface roughness. Limited results for the latter agree with past work by Achenbach. Results for cases of increasing stream turbulence line up not only with other high turbulence data but also with Dryden's long-established results for turbulence levels up to a few percent and thereby present some problems, both in the interpretation of the physical flow processes and in nomenclature for the criticality conditions involved.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 1982 

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