The impact of turbulence and turbine operating condition on the wakes of tidal turbines

RENEWABLE ENERGY

卷:165

Article

Ebdon, Tim¹  Allmark, Matthew J.¹  O'Doherty, Daphne M.¹  Mason-Jones, Allan¹  O'Doherty, Tim¹  Germain, Gregory²  Gaurier, Benoit² 

[1] Cardiff Univ, Sch Engn, Parade, Cardiff CF24 3AA, Wales

[2] IFREMER, Marine & Struct Lab, Ctr Manche Mer Nord, 150 Quai,Gambetta, F-62200 Boulogne Sur Mer, France

关键词: Turbine wake characteristics;    Turbulence;    Tip speed ratio;    CFD modelling;    Experimental analysis;   

DOI  :  10.1016/j.renene.2020.11.065

来源: Elsevier

【 摘 要 】

Before initiating a study on the interaction of multiple wakes, it is imperative that turbine wake hydrodynamics are studied in isolation. In this paper CFD computer simulations of downstream turbine wakes have been run using a scale-resolving hybrid turbulence model known as a detached eddy simulation. To allow validation of the CFD simulations the computer models were supported by flume measurements with a lab scale tidal stream turbine run at three tip-speed ratios and three turbulence conditions, varying both turbulence intensity and length-scale. From the study it was demonstrated that turbulence intensity has a significant impact on the wake development for both recovery and width. The turbulence length scales of between 0.25 and 1.0 rotor diameter did not have a significant impact on the wake. The turbine operating condition also had an impact on the resulting wakes. In the near wake, centreline velocity recovery was found to increase with increasing turbine thrust due to flow being diverted towards the turbine nacelle. For a volumetric averaged wake, greater power extraction was found to cause the greatest near-wake deficit. Wake width was found to increase with increasing tip-speed ratio (and therefore turbine thrust). (C) 2020 Elsevier Ltd. All rights reserved.y

【 授权许可】

Free