The effect of the number of blades on wind turbine wake - a comparison between 2-and 3-bladed rotors

The Science of Making Torque from Wind

Mühle, Franz^1 ; Adaramola, Muyiwa S.^1 ; Sretran, Lars^2

Department of Ecology and Natural Resource Management, Norwegian University of Life Science (NMBU), Ås

1430, Norway^1

Department of Energy and Process Engineering, Norwegian University of Science and Technology (NTNU), Trondheim

7491, Norway^2

关键词: Performance characteristics;    Power production;    Printing technologies;    Turbulence intensity level;    Velocity deficits;    Weight reduction;    Wind tunnel tests;    Wind turbine wakes;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/753/3/032017/pdf
DOI  :  10.1088/1742-6596/753/3/032017

来源: IOP

【 摘 要 】

Due to cost benefit and weight reduction, 2-bladed wind turbines have the potential to become more important for offshore wind applications. In order to optimize the arrangement of wind turbines in wind farms and for accurate forecasts of the power production, a detailed knowledge of the wake flow is needed. In this study, three different rotors with varying number of blades and similar performance behaviour have been designed and manufactured using the 3dimensional (3D) printing technology. The performance characteristics of these rotors as well as their wake features are measured experimentally in wind tunnel tests and compared. The velocity deficit is seen to vary only insignificantly for the wakes in distances of 3D (where D is the rotor diameter), 5D and 7D behind the turbine. However, higher turbulence intensity levels are recorded in the wake of the 2-bladed rotors. This could have potential for a faster wake recovery and thus a narrower turbine spacing.