Influence of centrifugal force and aerodynamic load on strain characteristics of wind turbine blades
DAI Yuanjun1,2,3*, GUO Cheng1, LI Baohua2, JIANG Jinbang1, WANG Cong2
1. College of Mechanical and Electrical Engineering, Xinjiang Agricultural University, Urumqi, Xinjiang 830091, China; 2. Mechanical College, Shanghai Dianji University, Shanghai 201306, China; 3. College of Energy Enginee-ring, Xinjiang Institute of Engineering, Urumqi, Xinjiang 830091, China
Abstract:A small horizontal axis wind turbine was taken as the research object, and the shear strain of the wind turbine blades was measured based on the 3D digital speckle correlation method(3D-DSCM, 3D digital speckle correlation method). The test mainly solves the problem that the strain ge-nerated by the small deformation of the blade surface which was caused by the wind turbine blade′s high-speed rotation and high-frequency vibration was not conducive to measurement. From the perspective of reliability, the test used a high-frame-rate digital speckle method to continuously collect data from a high-frame-rate camera to analyze the out-of-plane displacement of the blade under continuous working conditions. The accuracy of the photo analysis of the out of plane displacement of the blade under continuous working conditions could reach the measurement of the displacement change of the blade within 0.002 9 s. The results indicate that the strain concentration area of the blade structure is 0.7R from the radius of the blade root, and the strain value is 9.5%-19.3% higher than that of other positions.With the increase of centrifugal load and aerodynamic load, blade strain increases, and centrifugal force load is recognized as the main factor causing blade strain increase. The resonant driving effect causes the blade to produce alternating strain, and the alternating cycle law became worse as the strain amplitude increases exponentially.In addition, the resonant force produces focal effect at the blade root, which causes the blade strain to increase gradually along the chord stretch direction.
代元军,*,郭程,李保华,姜金榜,王聪. 离心力和气动力载荷对风力机叶片应变特性的影响[J]. 排灌机械工程学报, 2023, 41(6): 576-582.
DAI Yuanjun,*,GUO Cheng,LI Baohua,JIANG Jinbang,WANG Cong. Influence of centrifugal force and aerodynamic load on strain characteristics of wind turbine blades. Journal of Drainage and Irrigation Machinery Engin, 2023, 41(6): 576-582.