Leading Edge Vortex Development on Pitching and Surging Airfoils: A Study of Vertical Axis Wind Turbines
نویسنده
چکیده
Vertical axis wind turbine blades undergo dynamic stall due to the large 1 angle of attack variation they experience during a turbine rotation. Particle image 2 velocimetry on a pitching and surging airfoil was used to perform time resolved 3 measurements at blade Reynolds numbers near turbine operating conditions of 105. 4 These experiments were compared to simulations performed in the rotating turbine 5 frame as well as the linear, experimental, frame at a Reynolds number of 103 to 6 investigate rotational and Reynolds number effects. The flow was shown to develop 7 similarly prior to separation, but the kinematics of vortices shed post separation were 8 reference frame dependent. 9
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