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Reattachment of a Two-Dimensional, Incompressible Jet to an Adjacent Flat Plate*

Published online by Cambridge University Press:  07 June 2016

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Summary

As part of a general investigation into Coanda effect, a study has been made of the reattachment of a two-dimensional, incompressible, turbulent jet to an adjacent, inclined, flat plate. The jet separates from the boundaries at the slot lips and reattaches to the plate downstream, a phenomenon which is associated with the lowering of the pressure between the jet and the plate accompanying the entrainment of fluid there. It is found that the flow becomes independent of both the length of the plate and the Reynolds number when these parameters are sufficiently large: the flow, scaled with respect to the width of the slot, is then uniquely determined by the plate inclination. Two approximate theories are developed for the mean pressure within the separation bubble, the position of reattachment and the increase in volume flow from the slot: the agreement with experiment is fairly satisfactory. These theories are a development of Dodds's analysis for the reattachment of a jet to a plate offset from, and parallel to, the axis of the slot and, for the purpose of comparison, a limited study is also made of this flow.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society. 1960

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Footnotes

*

This report is abstracted from the thesis “Déviation d'un Jet Turbulent Incompressible par un Volet Incliné–Effet Coanda” presented by the first author to the Université Laval for the degree of M.Sc. The work was supported by the Defence Research Board of Canada under grant number 9550-05.

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