基于传统压电元件和含金属芯压电纤维的健康监测的研究

发布时间：2018-06-15 23:07

本文选题：Lamb波 + 结构健康监测　；参考：《南京航空航天大学》2017年硕士论文

【摘要】：基于Lamb波的结构健康监测技术能够在线实时地检测结构中的微小损伤,极大地维护了结构的安全性。本文利用传统压电元件和含金属芯压电纤维(MPF),深入研究了基于Lamb波的主动健康监测技术。首先,介绍了Lamb波的基本理论及其传播特性。分析了Lamb波的激励方法,对激励信号的参数进行了分析和选择。实现了软硬件的交互。其次,研究了层析法的原理,定义了不相关系数,并提出了损伤定位概率成像方法。根据结构健康监测系统的工作原理,搭建了实验平台,设计了损伤监测程序。计算了监测区域的空间分辨率,并分析了单损伤和多损伤的定位。再次,分析了针对不同检测原理的定位方法,并计算了空间分辨率与损伤识别之间的关系。研究了不相关系数与腐蚀程度的关系,判断了损伤的存在性,提出了腐蚀程度的识别方法。分析了椭圆因子对损伤定位结果的影响,并对腐蚀损伤和模拟损伤进行了定位。最后,针对传统方法需要Lamb波传播速度进行损伤定位的缺点,利用MPF花形传感器对Lamb波传感的方向性,提出了一种无需Lamb波波速信息的损伤定位方法。理论分析了MPF花形传感器的响应特性,通过冲击标定方法得到了花形传感器的电压响应幅值与Lamb波传播方向之间精确的函数关系。定义了一种损伤指标,并提出了基于角度识别的损伤定位方法,评估了监控区域的角度分辨率。实验结果表明,利用压电线阵和MPF花形传感器可以精确地对损伤进行定位成像。
[Abstract]:The structure health monitoring technology based on Lamb wave can detect the small damage in the structure in real time on line, which greatly maintains the safety of the structure. In this paper, the active health monitoring technology based on Lamb wave is studied by using traditional piezoelectric element and piezoelectric fiber with metal core. Firstly, the basic theory and propagation characteristics of Lamb wave are introduced. The excitation method of Lamb wave is analyzed and the parameters of excitation signal are analyzed and selected. The interaction of hardware and software is realized. Secondly, the principle of tomographic method is studied, the uncorrelated coefficient is defined, and the probabilistic imaging method of damage location is proposed. According to the working principle of the structural health monitoring system, the experimental platform was built and the damage monitoring program was designed. The spatial resolution of the monitoring area is calculated, and the location of single damage and multiple damage is analyzed. Thirdly, the location methods based on different detection principles are analyzed, and the relationship between spatial resolution and damage identification is calculated. The relationship between non-correlation coefficient and corrosion degree was studied, the existence of damage was judged, and the method of corrosion degree identification was put forward. The influence of ellipse factor on the damage location results is analyzed, and the corrosion damage and simulated damage are located. Finally, aiming at the disadvantage of the traditional method which requires the propagation velocity of Lamb wave to locate the damage, a damage localization method is proposed by using MPF flower sensor to the direction of Lamb wave sensor without the information of Lamb wave velocity. The response characteristics of MPF flower sensor are analyzed theoretically. The accurate functional relationship between the amplitude of voltage response and the propagation direction of Lamb wave is obtained by means of impulse calibration method. A damage index is defined and a damage location method based on angle recognition is proposed to evaluate the angular resolution of the monitoring area. The experimental results show that the damage location imaging can be carried out accurately by using the compression wire array and MPF flower sensor.
【学位授予单位】：南京航空航天大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TP212;TP274

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