Open AccessEffect of winglet geometry on horizontal axis wind turbine performance
Author(s) -
Mourad Mina G.,
Shahin Ibrahim,
Ayad Samir S.,
Abdellatif Osama E.,
Mekhail Tarek A.
Publication year - 2020
Publication title -
engineering reports
Language(s) - English
Resource type - Journals
ISSN - 2577-8196
DOI - 10.1002/eng2.12101
Subject(s) - wingtip device , turbine , geometry , tip speed ratio , horizontal axis , rotor (electric) , mechanics , vortex , vertical axis wind turbine , airfoil , physics , materials science , aerodynamics , mathematics , structural engineering , engineering , mechanical engineering , thermodynamics
Winglets (WLs) have recently been used to improve the performance of horizontal axis wind turbine (HAWT). The WL geometry is a key parameter for diverging blade tip vortices away from turbine blades and reducing induced drag. The present study focuses on the effect of winglet height ( H ) and toe angle ( α w ) on the turbine performance. The performance of a three‐bladed rotor of 1 m diameter with SD8000 aerofoil is numerically investigated using ANSYS 17.2 CFD on a polyhedral mesh. The model is hence validated by comparing results for power coefficient ( C pw ) with experimental values available in the literature. Four different values of H are considered while keeping α w constant at 0°. H of 0.8% R is proved to be the best height for performance enhancement. It increases C pw by 2.4% at tip speed ratio λ = 7. The toe angle effect is studied for upwind and downwind WLs. The results show that C pw increases as α w increases up to α w = +20° at all values of λ . C pw increases by 6% at λ = 7. Downwind WL always reduces C pw . The present results are well explained by the resulting vectors map near the blade tip. Using WL with the optimum H and α w , causes 6% increase in C pw as compared to rotor without WL.