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Two-Dimensional Flow at Right Angles to a Flexible Membrane

Published online by Cambridge University Press:  07 June 2016

B.G. Newman
Affiliation:
Department of Mechanical Engineering, McGill University, Montreal, Quebec
H.T. Low
Affiliation:
Department of Mechanical Engineering, McGill University, Montreal, Quebec
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Summary

Incompressible flow perpendicular to a flexible, impervious membrane has been studied for two-dimensional conditions. The membrane was mounted on relatively thin supports spaced c apart. Measurements of drag, base pressure and the frequency of membrane oscillation are presented for various lengths ℓ, and for two densities, of membrane. These parameters are related to one another theoretically and in particular Bearman′s universal correlation for Strouhal number agrees with the experimental results. It is found that for values of < 0.50 the drag is independent of membrane density. The drag decreases at larger values of and this is related to a periodic reattachment of the separated flow to the back of the membrane. For a given ℓ the drag is greatest when is very small and the membrane is almost flat.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society. 1981

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