基于小波多尺度分解的液固体系声发射信号特征分析  

Characteristics of Acoustic Emission Signals in a Liquid-Solid Two-Phase System with Wavelet Multi-Scale Analysis

作　　者：黄春燕[1,2] 蔡小舒[1] 苏明旭[1] 

机构地区：[1]上海理工大学能源与动力工程学院,上海200093 [2]上海理工大学学报编辑部,上海200093

出　　处：《高校化学工程学报》2014年第2期390-395,共6页Journal of Chemical Engineering of Chinese Universities

基　　金：国家自然科学基金重点项目(50836003;51176128)

摘　　要：在玻璃微珠-水两相搅拌体系中,利用宽带声发射传感器高速采集声发射信号,选择Db8小波基函数对信号进行10层分解,提取各尺度信号能量及能量占比等特征量,研究了特征量随搅拌速度、测量点位置、玻璃微珠质量和粒径的变化规律。结果表明,由玻璃微珠碰撞内壁面造成的声发射信号能量主要集中在D7-D10等四个尺度;随玻璃微珠质量增加,多测量点各尺度信号能量值较单测量点值显示出更良好的线性关系,且不同粒径下的能量占比特征量均各自趋于一个较为稳定的数值范围,可用来表征粒径变化的规律性。实验结果为后续利用声发射信号测量多颗粒系粒径提供了的实验依据。A broadband acoustic emission transducer was applied to acquire acoustic emission signals from aglass bead-water system. The signals acquired were processed by ten-level decomposition with Db8 waveletbasis function, and factors such as scaled signal energy and energy ratio were analyzed. Furthermore, the effectsof stirring speed, measurement location, glass beads weight and particle size were investigated. The resultsshow that the acoustic emission signal formed by the collision of the glass beads with the inner wall surface isfound in scales from D7 to D10. The results reveal that the scale information of the signals from themulti-measurement points gives a better linear relationship comparing with that from single measuring pointswhen the weight of the beads increases. Moreover, the energy ratio values of glass beads with different particlesizes are found to become stable individually, which can be used to characterize the particle size variation indifferent particle systems.

关 键 词：声发射 多尺度 特征分析 粒径 

分 类 号：TB302.5[一般工业技术—材料科学与工程]