Effect of steady and transient wind shear on the wake structure and performance of a horizontal axis wind turbine rotor
Effect of steady and transient wind shear on the wake structure and performance of a horizontal axis wind turbine rotor
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DOI：
10.1002/we.514
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发表时间：
2009-01
期刊：
影响因子：
4.1
通讯作者：
N. Sezer-Uzol;O. Uzol
中科院分区：
文献类型：
--
作者：
N. Sezer-Uzol;O. Uzol
本文研究了定常和瞬态自由流风切变对水平轴风力涡轮机转子尾迹结构和性能特性的影响。为此，使用了一种新的三维非定常涡面元法势流求解器，其基于自由涡尾迹方法AeroSIM+。利用美国国家可再生能源实验室非定常空气动力学实验数据对该程序进行了验证。涡核模型的影响，核心的大小，膨胀，和细丝拉伸扭矩和推力预测进行了研究。三种不同的风切变情况，即研究了均匀入流（无风切变）、使用幂律速度廓线的稳定垂直风切变（正常风廓线，NWP）和瞬时极端风切变（EWS）。结果表明，风切变的存在会在涡轮机转子下游产生非常复杂的尾流结构，具有显著的非对称性、流向涡量产生和非周期性。此外，叶片经受不对称的表面压力变化，这又导致由涡轮机产生的功率和推力水平的高幅度波动。版权所有© 2011约翰威利父子有限公司.
This paper presents an investigation of the effect of steady and transient free-stream wind shear on the wake structure and performance characteristics of a horizontal axis wind turbine rotor. A new three-dimensional unsteady vortex-panel method potential flow solver based on a free-vortex wake methodology, AeroSIM+, is used for this purpose. The code is validated using the experimental data from the National Renewable Energy Laboratory Unsteady Aerodynamics Experiments. The effects of vortex core model, core size, expansion, and filament stretching on torque and thrust predictions are investigated. Three-different wind shear cases, i.e., uniform inflow (no wind shear), steady vertical wind shear that uses a power law velocity profile (Normal Wind Profile, NWP) and transient Extreme Wind Shear (EWS), are investigated. The results show that the existence of wind shear can create a very complex wake structure with substantial asymmetries, streamwise vorticity generation, and non-periodicities downstream of the turbine rotor. In addition, the blades are subjected to asymmetrical surface pressure variations that in turn result in high amplitude fluctuations in power and thrust levels generated by the turbine. Copyright © 2011 John Wiley & Sons, Ltd.