Study on effect of blade tip slot on blade tipflow field of the wind turbine

Abstract

Abstract: Taking the 1/8 scaled model of the NREL Phase VI blade as the research object, three annular slots from the leading edge to the tip surface of the blade are designed in the blade tip region to change the distribution of the blade tip flow field. Using the CFD method, the pressure distribution on the blade tip surface and the development process of the tip vortex are analyzed through the speed change, and the influence of the blade tip slot on the tip vortex of the wind turbine is studied. The research results show that when the speed is lower than 900 r/min, the blade tip slot has little effect on the aerodynamic performance of the blade. When the speed is higher than 900 r/min, the blade tip slot can reduce the strength of the vortex core, accelerate the tip vortex dissipation, and increase the aerodynamic efficiency of the blade. The air flow jetted from the annular slots has a significant blocking effect on the incoming flow, and can reduce the axial velocity in the wake region. In terms of accelerating the dissipation of the tip vortex and reducing the strength of the tip vortex, the slot at the blade tip of the wind turbine is considered to be an effective design when the speed is higher than 900 r/min.

Key words: blade tip slot, numerical simulation, blade tip vortex dissipation, flow control, Vortex core

CLC Number:

TK83

YANG Rui, WEN Wei-yue, ZHOU Nan-nan, YANG Wei, GU En-xin. Study on effect of blade tip slot on blade tipflow field of the wind turbine[J]. Journal of Lanzhou University of Technology, 2021, 47(6): 38-44.

References

[1] XIAO Jingping,WU Jie,CHEN Li,et al.Particle image velocimetry (PIV) measurements of tip vortex wake structure of wind turbine [J].Applied Mathematics and Mechanics(English Edition),2011,32(6):729-738.
[2] YANG Zifeng,SARKAR P,HU Hui.An experimental investigation on the wake characteristics of a wind turbine in an atmospheric boundary layer wind [C]//29th AIAA Applied Aerodynamics Conference.Hawail:AIAA,2012.
[3] 吴江海,朱呈勇,陈恺,等.不同叶尖构型对大型风力机叶片气动特性的影响 [J].工程热物理学报,2020,41(11):2742-2746.
[4] MHLE F,BARTL J,HANSEN T,et al.An experiments study on the effects of winglets on the tip vortex interaction in the near wake of a model wind turbine [J].Wind Energy, 2020,23(5):1286-1300.
[5] 杨振涛,汪建文,冬雪青,等.小翼对风力机叶尖涡运动轨迹的影响研究 [J].工程热物理学报,2014,35(12):2398-2401.
[6] WANG Haipeng,ZHANG Bo,QIU Qinggang,et al.Flow control on the NREL S809 wind turbine airfoil using vortex generators [J].Energy,2016,118(1):1210-1221.
[7] 马兴宇,明晓.风力机叶尖涡特性及其控制 [J].南京航空航天大学学报,2011,43(5):635-639.
[8] HAN Y O,LEISHMAN J G.Investigation of helicopter rotor-blade-tip-vortex alleviation using a slotted tip [J].AIAA Journal,2004,42(3):524-535.
[9] MARGARIS P,GURSUL I.Vortex topology of wing tip blowing [J].Aerospace Science and Technology,2010,14(3):143-160.
[10] 杨胜兵.开孔对翼型及风力机气动性能影响的研究 [D].兰州:兰州理工大学,2020.
[11] 龚志斌,李杰,张恒.翼尖开孔吹气流动控制数值模拟研究 [J].航空计算技术,2015,45(4):21-24.
[12] 韩彦军,叶舟,徐学昊,等.尾缘射流对翼型气动性能的影响 [J].热能动力工程,2020,35(10):131-139.
[13] 高翔,胡骏,王志强.叶尖射流对风力机叶尖流场影响的数值研究 [J].航空动力学报,2014,29(8):1863-1870.
[14] 朱海天, 郝文星, 李春,等.零质量射流技术控制垂直轴风力机流动分离的数值研究 [J].应用力学学报,2018,35(6):1192-1199.
[15] 郝文星,朱海天,李春,等.合成射流控制策略对垂直轴风力机性能影响研究 [J].热能动力工程,2019,34(9):41-48.
[16] 王珑,王同光.风力机设计及其空气动力学问题 [J].中国科学:物理学力学天文学,2013,43:1579-1588.
[17] 王福军.水泵与泵站流动分析方法 [M].北京:中国水利水电出版社,2020.