Investigation and optimization of winglets for hawt rotor blades


Elfarra M. A. , Akmandor I. S. , Sezer Uzol N.

9th European Conference on Turbomachinery: Fluid Dynamics and Thermodynamics, ETC 2011, İstanbul, Turkey, 21 - 25 March 2011, vol.1, pp.585-594 identifier

  • Publication Type: Conference Paper / Full Text
  • Volume: 1
  • City: İstanbul
  • Country: Turkey
  • Page Numbers: pp.585-594
  • Middle East Technical University Affiliated: Yes

Abstract

Copyright © 2011 Local Organising Commitee.The main purpose of this paper is to optimize winglet geometry by using CFD with Genetic Algorithm and study its effects on power production. For validation and as a baseline rotor, the NREL Phase VI wind turbine rotor blade is used. The Reynolds-Averaged Navier-Stokes equations are solved and different turbulence models including the Spalart-Allmaras, k-e Launder-Sharma, k-e Yang-Shih and SST k-ω models are used and tested. The results of the power curve and the pressure distribution at different spanwise sections of the blade are in good agreement with the experimental data especially for the k-e Launder-Sharma. In the winglet design, the variable parameters are the cant and twist angles of the winglet. Multipoint optimization is carried out for three different operating wind speeds and 24 samples are obtained for each one. The final optimized winglet showed around 9% increase in the power production.