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The Aerodynamic Efficiency of Windmills

Published online by Cambridge University Press:  07 June 2016

G M Lilley*
Affiliation:
Department of Aeronautics and Astronautics, University of Southampton
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Summary

The paper reproduces the results of an earlier report on the vortex theory of windmills and follows that theory through to establish the aerodynamic design procedure for a horizontal axis windmill. The results are shown to differ considerably from those given in a recent paper by Griffith and the differences are explained. The main conclusion is that, when full allowance is made for the drag of the blades, hub and tip losses, and losses due to interference with the support tower, the power output coefficient or efficiency of a horizontal axis windmill cannot exceed 30 to 35 per cent, as compared to an ideal efficiency of 59 per cent.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society. 1978

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References

1 Griffith, R T The effect of aerofoil characteristics on windmill performance. Aeronautical Journal, Vol 81, No 799, p 322, July 1977.CrossRefGoogle Scholar
2 Iwasaki, M The experimental and theoretical investigation of windmills. Rep. Res. Inst. App. Mech. (Japan) Vol II, No 8, Dec. 1953.Google Scholar
3 Sanuki, M Studies of biplane wind vanes, ventilator tubes and cup anemometers. Papers in Meteorology and Geophysics (Japan), Vol 1, No 2-4, pp 279290, Dec. 1950.Google Scholar
4 Lilley, G M Rainbird, W J A preliminary report on the design and performance of ducted windmills. C.A. rep. No 102, April 1956.Google Scholar
5 Theodorsen, T Theory of Propellers. McGraw Hill, 1948.Google Scholar
6 Lock, C N H Yeatman, D Tables for the use in an improved method of airscrew strip theory calculation. T and M 1674, 1935.Google Scholar
7 Goldstein, S On the vortex theory of airscrews. Proa. Roy. Soc. (A), Vol 123, 1929.Google Scholar