Wind-tunnel study of the wake behind a vertical axis wind turbine in a boundary layer flow using stereoscopic particle image velocimetry

Wake Conference 2015

Rolin, V.^1 ; Porté-Agel, F.^1

Wind Engineering and Renewable Energy Laboratory, Ecole Polytechnique Fédérale de Lausanne, Switzerland^1

关键词: Boundary layer effects;    Energization;    Stereo particle image velocimetry;    Stereoscopic particle image velocimetry;    Tip speed ratio;    Turbulence level;    Velocity deficits;    Vertical axis wind turbines;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/625/1/012012/pdf
DOI  :  10.1088/1742-6596/625/1/012012

来源: IOP

【 摘 要 】

Stereo particle image velocimetry is used in a wind-tunnel to study boundary layer effects in the wake behind a vertical axis wind turbine. The turbine is a three-bladed giromill with a solidity of 1.18. The wake is studied for a tip speed ratio of 2 and an average chord Reynolds number of 1.6 × 104. The velocity deficit and turbulence levels in the horizontal plane are observed to be strongly asymmetrical with two strong peaks corresponding to the two halves of the rotor where blades move either towards the oncoming flow or away from it. The stronger peak is measured behind the blades moving upstream, however this region also benefits from a greater rate of re-energization. Due to the incoming boundary layer profile, momentum is also entrained downwards into the wake from above and AIDS with the recovery of the core of the wake.