摘要
声发射具有对缺陷起始和扩展探测灵敏的特点,适用于复合材料薄板损伤检测,其中定位方法的研究是关键技术之一。文章结合光纤传感技术,设计并构建了声发射检测系统,实现了复合材料薄板的损伤源定位。基于三角定位原理,进行分布式光纤传感布置,在复合材料薄板上方获取损伤信号。然后将测得的信号依次利用Daubechies10小波和Gabor小波进行背景去噪和信号峰值提取,从而获得损伤源释放的A0模态兰姆波传播到各个传感器的精确时间。最后由到达时间依据三角损伤定位算法建立非线性方程组,通过计算即可求出损伤源位置。相比其它方法,该方法具有非接触、无需测量对象材料参数的优点,在复合材料薄板损伤检测应用中有重要意义。
Acoustic emission can be applied for composites sheet damage detection because of its being sensitive to the defect＇s generation and expansion, and damage location is the key technology in acoustic emission. This paper provided an acoustic emission detection system combined with optical fiber sensing technology, identified the location of damage sources in composites sheets. The distributed optical fiber sensors were arranged on the top of composites sheet based on triangulation principle to detect damage signals. Then, Daubechies10 wavelet and Gabor wavelet were used to denoising and acquire signal peak to obtain the propagation time of Lamb mode（A0）. Finally, the location of destructive source was obtained by computing for non-linear equations, which were established by the time of arrivals based on triangulation. This method had the advantage over other methods, such as non-contact and no use of material parameters. It was an important method to detect composites sheet damage.
出处
《无损检测》
2011年第12期54-57,61,共5页
Nondestructive Testing
基金
南京航空航天大学基本科研业务费专项科研项目资助项目(NS2011017)
南京航空航天大学2010年度研究生创新基地(实验室)开放基金资助项目(201002011)
关键词
声发射
光纤传感
复合材料
波群速度
Acoustic emission
Optical fiber sensor
Composites
Group velocity
