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Two-dimensional flow past bluff flexible membranes of low porosity

Published online by Cambridge University Press:  04 July 2016

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

This paper considers two-dimensional flow past flexible membranes whose supports are aligned at right angles to the flow. Unlike a previous study of bluff impervious membranes, the present membranes are slightly porous having a porosity similar to that of parachutes. The drag and base pressure have been measured for various lengths and for a variety of fabrics. The results have been correlated by two theories which are extensions of those already published. When the porosity is not too small the results are shown to depend only on the total volume flow through the membrane. The tendency for the membrane to oscillate in harmony with regular vortex shedding is reduced by the porosity and increased by the length of the membrane. Above a certain porosity oscillation is inhibited for all membrane lengths.

Type
Research Article
Information
The Aeronautical Journal , Volume 90 , Issue 898 , October 1986 , pp. 313 - 334
Copyright
Copyright © Royal Aeronautical Society 1986 

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Footnotes

*

Dept of Mechanical & Production Engineering, National University of Singapore.

†

McGill University.

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