Effects of geometry and tip speed ratio on the HAWT blade's root flow

The Science of Making Torque from Wind 2012

Akay, Bura^1 ; Micallef, Daniel^2 ; Ferreira, Carlos J. Simão^1 ; Van Bussel, Gerard J.W.^1

Wind Energy Section, Faculty of Aerospace Engineering, Delft University of Technology, Kluyverweg 1, Delft

2629HS, Netherlands^1

University of Malta, Faculty of Eng., Department of Mechanical Eng., Msida

MSD 2080, Malta^2

关键词: Blade geometry;    Bound vorticities;    Circulation distribution;    Flow behaviors;    Flow properties;    Tip speed ratio;    Velocity field;    Vortex evolutions;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/555/1/012002/pdf
DOI  :  10.1088/1742-6596/555/1/012002

来源: IOP

【 摘 要 】

In this study, the effect of the parameters playing a role in the root flow behavior of HAWT are only partly understood. To better reveal the root flow properties, this study presents the progression of HAWT blade root flow at two different blade geometries and at two different tip speed ratios. The effects of the geometry and the tip speed ratio on the root flow behavior and on the evolution of the root flow features are investigated. This study aims to answer the following questions: (i) What are the effects of the blade geometry and tip speed ratio on the root flow behavior? (ii) How are the blade wake and the root vortex evolution affected by the change of these parameters? The analysis of the velocity fields shows that the radial flow behavior changes with different blade geometries but a remarkable difference in the radial flow behavior is not observed with the change of tip speed ratio. The formation of the wake is different at three test cases because of different loading that the blades are encountered. From the circulation distribution along the blades, while a strong root vortex can be observed in Blade 1, the bound vorticity along Blade 2 builds up gradually when moving outboard, and do not show a trace of a strong root vortex.