摘要
本文在低速风洞开口实验段,采用粒子图像测速技术(PIV)对水平轴风力机叶尖涡流场进行测试。由于相机拍摄区域较小,不能得到风力机叶尖涡流场的整体传播规律,因此实验采用三窗口拼接技术进行研究。通过对多组PIV图像进行时间平均,发现在不同尖速比工况下,流场中均有明显的叶尖涡结构,但只有在靠近叶片附近的窗口涡结构比较清晰,随着尖速比增加叶尖涡涡核径向位置升高,中心尾迹区域扩大。对多组PIV图像进行位置平均,计算同一子午面叶尖涡涡核轴向位移,得到风力机叶尖涡脱落基频,但由于叶尖涡流场轴向速度的衰减,计算值存在误差。添加结构合适的小翼后,风力机功率升高,叶尖涡的脱落基频增大,涡量减小。
The PIV measure of the Horizontal axis wind turbine blade tip vortices was carried out using particle image velocimetry （PIV） at wind tunnel opening. The camera can only shoot very small area and it can＇t get the whole field propagation of tip vortex, so we use three- window splicing technology to improve the experiment. Through carrying on the time average to many group＇s PIV images, we find that each flow field has three obvious tip vortices structure in different tip speed ratio, but only the vortex structure near the blade＇s window is clear. Along with the tip speed ratio increase and tip vortex core radial position increases, the central wake region expand. By carrying on the position average to many group＇s PIV images and calculating tip vortex core axial displacement, we get the wind turbine blade tip vortex shedding frequency, but the result has the error due to the attenuation of axial velocity of tip vortex. After adding appropriate tip vane, the wind turbine power increase, the tip vortex shedding frequency increase and the vorticity decrease.
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2013年第2期258-261,共4页
Journal of Engineering Thermophysics
基金
教育部博士点基金资助项目(No.20091514110001)
国家自然科学基金资助项目(No.50976047)
关键词
水平轴风力机
叶尖涡
叶尖小翼
多窗口
涡量
horizontal axis wind turbine
tip vortex
tip vane
multi-windows
vorticity
