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The mixing of three-dimensional turbulent wakes and boundary layers

Published online by Cambridge University Press:  04 July 2016

A. Moghadam
Affiliation:
Department of Engineering, University of Cambridge
L. C. Squire
Affiliation:
Department of Engineering, University of Cambridge

Abstract

A fundamental study is presented of the three-dimensional aspects of the wake/boundary layer interaction as it occurs on high-lift wings, particularly the slat-wake/wing boundary layer interaction. A digital system for measuring and recording all the components of the mean velocity and the Reynolds stress tensor using a triple hot-wire probe has been developed. This system has been tested and has been used to measure the interaction between the wakes of swept aerofoils and the fully turbulent boundary layer developing on a flat plate. An important and interesting result of all the tests is the rapid decay of the three dimensionality in the wake, so that in many cases the actual interaction is almost two-dimensional. Two cases of three-dimensional interaction have been simulated. In one case the interaction is fully three-dimensional while in the other case it can be assumed to be quasi three-dimensional. For the quasi three-dimensional confluent flow, the measured results have been compared with the predictions of the two-dimensional form of K-ε and algebraic stress turbulence models. The overall agreement between the measured and predicted results is good. However, for the turbulence flow field the agreement is less satisfactory in the initial mixing region where the three-dimensionality is strong and it is also poor in the wall boundary layer.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 1989 

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