Andreau principle? (2004-01-13)

[Old Forum Archivist]

Gentlemen:



In the 1953 edition of The Engineer I was intrigued to read of a 100kW wind driven generator deployed in St. Albans in England that made use of the 'Andreau' principle in which the wind-driven propeller blades were hollow. The trailing tips of the blades were provided with openings through which the air was expelled by centrifugal action as the propeller was rotated by the wind.



According to the article, air flow was induced up a vertical converging duct to the hub of the propeller. The air was admitted through vents at the lower end of the duct and passed through an air turbine which drove a vertical shaft alternator mounted at the base of the duct. The duct casing formed a support for the propeller and was stayed by twelve guide ropes.



I would be most interested to lean what possible advantage such a design might have had back then, and more importantly, why such a design has been abandoned in favour of modern propeller designs.



I think the subject might be most interesting for the readers of www.e4engineering.



Please email me with any comments to david.wilson@centaur.co.uk



Sincerely:



Dave Wilson

Editor

www.e4engineering

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