风机叶片复合材料裂纹损伤的声发射实验研究

Experiment Research on Crack Damage of Composite Wind Turbine Blade

利用声发射技术实现监测和破坏识别,关键在于提前获得各种破坏形式的声发射信号特征。针对这一目的,设计了风力机叶片常见破坏位置的撕裂破坏试件,通过对同种材料("1-4"材料)的两种破坏模式(Ⅰ型裂纹,Ⅱ型裂纹)进行比对分析,研究表明,同种材料铺层("1-4"材料)的Ⅰ型裂纹、Ⅱ型裂纹呈现出不同的特征参数。Ⅰ型裂纹破坏后断面上玻璃纤维断裂和层合板基体脱胶,Ⅱ型裂纹破坏后的断面上纤维是基本完好的,被撕开的是层合板基体。可以利用该结论有效地对风力机叶片同种材料("1-4"材料)的两种破坏模式(Ⅰ型裂纹,Ⅱ型裂纹),为声发射技术在线监测风力机叶片材料提供了一种新的途径。

The key is early to achieve acoustic emission signal in all kinds of destructive forms by using acoustic emission technique to monitor and i-dentify the materials. Aim at this purpose, the pa-per designed a series of samples which contained common damaging forms and points in the blades of large scale wind turbine. According to compare the different damaging forms in the same kind ma-terials （number 1 to 4）,it concluded that the two damaging cracks in the same kind materials ap-peared different characteristic parameters. After the samples were damaged, to the mode-Icrack, we could see the glass fibers were abrupt and the matrix of the layers were damaged on the cross section. But to the mode - Ⅱ crack, the glass fibers were basically intact and the matrix of the layer were rived. This conclusion can effectively monitor the typical type Ⅰ and type II cracks in the same kind materials, and provided a new approach for the acoustic emission on-line monitoring the wind turbine blade materials.