DocumentCode :
12484
Title :
Vortex methods to answer the need for improved understanding and modelling of tip-loss factors
Author :
Branlard, Emmanuel ; Dixon, Kristian ; Gaunaa, Mac
Author_Institution :
Wind Energy, Denmark
Volume :
7
Issue :
4
fYear :
2013
fDate :
Jul-13
Firstpage :
311
Lastpage :
320
Abstract :
Standard blade element momentum (BEM) codes use Prandtl´s tip-loss correction which relies on simplified vortex theory under the assumption of optimal operating condition and no wake expansion. The various tip-loss functions found in the literature are listed. A simple comparison between them shows important differences in Annual Energy Production which reveal a large uncertainty in current BEM-based computations. A new tip-loss correction for implementation in BEM codes has been developed using a lifting-line code to account for the effect of wake expansion, roll-up and distortion under many operating conditions. A database of tip-loss corrections is established for further use in BEM codes. This model is closer to the physics of the flow and hence, a better assessment of the performance of wind turbines by this method is expected.
fLanguage :
English
Journal_Title :
Renewable Power Generation, IET
Publisher :
iet
ISSN :
1752-1416
Type :
jour
DOI :
10.1049/iet-rpg.2012.0283
Filename :
6547871
Link To Document :
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