基于模态理论降低声发射源定位误差的方法

摘要

以玻璃纤维复合材料为研究对象,对声发射波在玻璃钢中传播的频率变化规律进行了研究,发现距声发射源不同位置采集到的声发射波的主要频率范围并不相同;根据模态声发射理论中不同频率段声发射信号传播特性不同的结论,对声发射波经不同通频带滤波器滤波后到达各传感器的时间差的线性关系进行了比较分析,得出声发射波到达时间的精确提取方法,发现模态滤波定位误差明显低于传统时间提取定位误差.%With glass fiber composite material as the research object,the regularity of frequency variation of acoustic emission wave in glass reinforced plastics was studied,and it was found that acoustic emission wave attenuation frequencies collected from different locations of the acoustic emission sources were concentrated in different areas.According to the theory of modal acoustic emission that acoustic emission signal propagation characteristics are different in different frequency ranges,acoustic emission wave was filtered by different passband filters,and the linear relationship about its time difference to each sensor were analyzed for the purpose of comparison,and hence a precise method of extracting the acoustic emission wave arrival time was obtained and it was found that the error of the mode filtering was significantly lower than the traditional time.