风力机叶片蒙皮微裂纹早期损伤演化分析

Early Damage Evolution Analysis of Micro-Cracks on the Skin of Wind Turbine Blade

针对风力机叶片在成型过程中会无法避免的存在大量的微裂纹进而导致叶片断裂的问题,分析微裂纹在拉伸条件下温度与应力的变化情况。使用万能试验机对表面含有预制微裂纹的叶片试件进行拉伸试验,同时采用红外热像仪采集试件试验过程的温度场;再利用ANSYS软件对相同结构进行仿真得到其应力场,对比试验与仿真过程中温度与应力的变化情况。结果表明,微裂纹初始扩展过程中,温度升高较为缓慢,而后随着应力的逐渐增加,温度升高更为明显,并在加载后期出现一个大幅度的温度升高现象,且整个过程中温度与应力都呈增加趋势,有助于风力机叶片微裂纹早期损伤的检测,提高风力机的运行效率,保证风力机的健康运行。

In order to solve the problem that there are a lot of micro-cracks in the manufacturing process of the wind turbine blades,which leads to the blade fracture,the temperature and stress fields of the micro-crack under the tensile condition were analyzed.Tensile test of the specimen with prefabricated micro-crack on the surface was carried out using an universal testing machine,and the temperature field of the specimen was collected by the infrared thermal imager.Then the ANSYS software was used to simulate the same structure to obtain the stress field,and the temperature and stress changes during the test and simulation were compared.The results show that during the early stage of micro-cracks propagation,the temperature rises slowly,and then with the gradual increase of stress,the temperature rise is more obvious,a large temperature rise occurs during the later stage.The temperature and stress are all increased during the whole process.It helps to detect the early damage of micro-cracks in wind turbine blades,improves the operating efficiency and ensures the healthy operation of wind turbines.