通过对小型风力发电机叶片进行停转与运转状态下多种损伤工况的数值模拟,进行模态分析,以此研究叶片损伤识别与定位的方法,并提出加权柔度曲率指标,建立加权柔度曲率值与刚度损伤值的拟合函数。研究得到：首先通过自振频率的变化可判断叶片是否发生损伤;其次无论叶片是否发生损伤,随着叶片转速的增大,其固有频率都会增大。加权柔度曲率值在损伤位置处产生突变,表现为尖峰凸起,且随着损伤程度的加剧,损伤位置处尖峰凸起越发明显。
Abstract
Based on the numerical simulation of various damage conditions of the small fan blades in the stalling and running states, the modal analysis was carried out to study the method to identify and locate the blade damage, and the author calculated the weighted flexibility curvature index to establish Fitting function of weighted flexibility curvature value and stiffness damage value. The results are as follows: firstly, whether the blade is damaged can be judged by the change of natural frequency. Secondly, regardless of the blade damage, as the blade speed increases, its natural frequency will increase. If the weighted flexibility curvature value mutates at the damage location, there will be a peak protrusion, and along with the increasing of the degree of damage, the peak protrusion becomes more obvious. At the same time, the fitting function proposed in this paper has minor errors and high reliability, which can locate the damage of the blade and quantify the degree of damage.
关键词
风力发电机 /
叶片 /
数值模拟 /
模态分析 /
加权柔度曲率值
Key words
wind turbines /
blades /
numerical simulation /
modal analysis /
weighted flexibility curvature value
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参考文献
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基金
内蒙古自治区自然科学联合基金（2018LH05008）
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