摘要
利用混沌系统的参数敏感性与噪声免疫性,提出了一种以Poincare截面为混沌判据的弱导波信号检测系统,实现了管道小缺陷的识别与评估。首先,结合分岔分析与Poincare截面获取混沌阈值,完成了检测系统的参数设定。然后,通过仿真分析验证了以Poincare截面为混沌判据的检测系统的噪声免疫能力与参数敏感性。最后,开展了超声导波检测管道中小缺陷的试验研究,并将实测信号作为驱动力的扰动项输入到检测系统中,通过Poincare截面的突变有效地识别出小缺陷引起弱导波信号。为了对缺陷进行定位和评估,一种快速的二分法被用来进行缺陷定位。同时,通过在Poincare截面上构造胞空间,计算出Poincare截面上相点所占胞元数定义为损伤指标,该损伤指标在一定范围内与损伤程度具有简单的线性关系,可为缺陷大小评估提供参考。
A weak ultrasonic guided wave signal identification system was proposed based on the Poincare section of a Duffing chaotic system to realize the identification and evaluation of small pipeline defects,in which the good sensitivity of the Duffing chaotic system to weak signals of the same frequency was utilized.The critical state of the Duffing chaotic system’s transition from periodic state to chaos was determined through bifurcation analysis,and the critical state was set as an inspection system.Then,the ultrasonic guided waves based NDT were carried out in a pipeline,and the measured signal was added to the inspection system as a disturbance item of the driving force.The study shows that the Poincare cross section of the system is a point,indicating that the system maintains a periodic state when there is only a noise signal in the detection signal but no guided wave signal in it,but the Poincare cross section of the system will suddenly change to a certain hierarchical point collection when the detection signal contains a weak guided wave signal.This feature can be used to identify weak guided wave signals and to identify small defects in the pipeline.In order to quantitatively analyze the defects,the cell space on the Poincare section was constructed and the number of cells occupied by the phase points was counted and defined as the damage index.Experiments studies show that there is a simple linear relationship between the damage index and the defect size.
作者
成梦菲
张伟伟
王晶
闫晓鹏
马宏伟
CHENG Mengfei;ZHANG Weiwei;WANG Jing;YAN Xiaopeng;MA Hongwei(College of Mechanical and Vehicle Engineering,Taiyuan University of Technology,Taiyuan 030024,China;Mechanic Department,Taiyuan University of Science&Technology,Taiyuan 030024,China;Department of Civil Engineering,Dongguan University of Technology,Dongguan 523808,China)
出处
《振动与冲击》
EI
CSCD
北大核心
2022年第2期161-168,共8页
Journal of Vibration and Shock
基金
国家自然科学基金(11872261)
山西省自然科学基金(201801D121012)。
