【作者】 常丽平；

【导师】 李成；

【作者基本信息】 郑州大学 ， 机械设计及理论， 2013， 硕士

【摘要】 随着全球经济的快速发展,能源和环境问题成了当今世界共同面临的两个重大问题,人类在大力发展可再生能源方面已经达成共识。风能作为一种绿色无污染的新能源已引起了世界各国的注意并日益受到重视,而风力发电是目前风能利用的主要形式。在整个风力发电系统中,叶片是最为关键的部件之一,同时也是受力最为复杂的部件。叶片的可靠性直接关系到整个系统的安全运行,叶片的转速、尖速比等直接影响风力发电机的性能。本课题以某一水平轴的复合材料风力发电叶片为研究对象,运用Ansys Workbench软件平台中的流体计算软件CFX对其在不同工况下进行流固耦合数值模拟,并分析不同的因素对叶片流固耦合结果的影响。本文首先对叶片进行了振动模态分析,并通过与现有文献的结果对比验证了叶片模型的正确性。通过对在一定风速和尖速比范围内的叶片的流固耦合计算结果进行对比,结果显示在不同的风速情况下叶片有唯一的最佳尖速比：在最佳尖速比情况下,计算分析叶片的应力和变形随叶片厚度的变化情况；最后在原有叶片的基础上改变叶片的翼型相对厚度和叶片长度,并对其进行流固耦合模拟。对比不同叶片的流固耦合模拟计算结果发现：不同叶片的应力和变形云图变化不大。叶片的应力集中发生在叶片压力面上距离叶尖约三分之一叶长部位,该部位是叶片的危险截面,易发生疲劳断裂；叶片的变形是从叶根到叶尖呈梯度分布。叶片长度的增加会加剧叶片的应力集中和变形情况,而叶片翼型相对厚度和弦长的增大会在一定程度上改善叶片的应力集中和变形情况。更多还原

【Abstract】 With the rapid development of global economy, energy and environment have become the major problems confronted by the world nowadays. It has reached a consensus for developing renewable energy vigorously. As a green, non-polluting energy, wind energy has attracted the attention of the world and has been received increasing attention. And wind power is the main form of wind energy utilization.The blade is one of the most critical components in the wind power generation system, whose stress state is complex. The reliability of blade is directly related to the safe operation of the entire system, the rotational speed and tip speed ratio is a directly affects the performance of the wind turbine. A certain horizontal axis composite wind turbine blade was used as the main research model, and the paper simulated its fluid solid interaction by CFX on SNSYS Workbench software, and analyzed the changes of the results under different conditions.Firstly, this paper analyzed the modal of the blade, and verified exactness of the modal by comparing with the results of existing paper. The results showed that it had a unique optimal tip speed ratio by contrasting the results under different wind speed. Blades under different thickness were analyzed by fluid structure interaction simulation in condition of the optimal tip speed ratio. At the end, the paper analyzed the blades with different aerofoil parameter and length.The result showed there was little change in the stress and deformation contours of different blades. The stress concentrations of blades appeared at about one-third of the blade length from the blade tip under compressive stress, which can easily lead to fatigue failure. And the deformation of the blade from root to tip emerges in gradient distribution. The increase of the blade length exacerbated the stress concentration and deformation of the blade, and the increase of the aerofoil parameter improved the stress concentration and deformation of the blade to some extent.更多还原