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The Effect of Base Bleed on the Flow behind a Two-Dimensional Model with a Blunt Trailing Edge

Published online by Cambridge University Press:  07 June 2016

P. W. Bearman
P. W. Bearman*
Affiliation:
Cambridge University Engineering Laboratory*
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Summary

The effects of base bleed on the flow about a two-dimensional model with a blunt trailing edge were examined at Reynolds numbers, based on model base height, between 1·3×104 and 4·1×104. The ratio of boundary layer thickness at the trailing edge to half the model base height was approximately 0·4. Measurements were made of base pressure, vortex shedding frequency and the distance to vortex formation. With a sufficiently large bleed quantity the regular vortex street pattern disappeared and the base drag of the section was reduced to about a third of its value without bleed. The base pressure was found to vary linearly with the inverse of the vortex formation distance. Results of a previous splitter plate investigation were found to agree closely with those of the present experiments.

Type
Research Article
Information
Aeronautical Quarterly , Volume 18 , Issue 3 , August 1967 , pp. 207 - 224
Copyright
Copyright © Royal Aeronautical Society. 1967

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