埋入式压电陶瓷传感器力学模型及试验验证

Mechanical Modeling and Experimental Validation on Embedded Piezoelectric Ceramic Sensor

目的验证采用集总质量法建立PZT晶体简化传感模型并进行数值模拟的正确性.方法以压电陶瓷晶体为研究对象,以压电本构方程为出发点,推导出PZT传感器正压电效应的电荷表达式,进行简谐荷载激励下传感效应数值分析及试验验证.结果根据压电方程和振动方程建立的智能骨料的传感力学模型与试验误差为12.18%,在工程应用中是可行的.PZT片在混凝土包围下作用力越大,传感信号也越大.PZT主要沿轴向振动,在径向受力较小基本忽略,骨料的径向尺寸对PZT信号影响不大证明了运用所建立的传感模型能够有效地模拟检测PZT的正压电规律,同时PZT片的电压输出特性与作用力的大小、PZT尺寸以及边界条件有关.结论在PZT传感模型中,由压电方程和振动方程的联合求解,可以快速得到PZT的传感信号,通过试验对比证明了力学模型的正确性.

This paper presents a mechanical modeling and experimental validation on embedded piezoelectric ceramic sensor. The piezoelectric ceramic （Zirconium titanic lead, PZT）is embedded into a small volume of concrete to make an artificial aggregate and used as a smart sensor. The purpose of the paper is to set up a simple sensing model of the smart aggregate by lump mass method. The developed model is numerically ana- lyzed and experimentally validated. Based on the piezoelectric constitutive equations and equation of motion, the expression of electric charge is derived and the sensing effect of the smart sensor excited by a harmonic load is numerically analyzed. A group of experiments are carried out to validate the efficiency of the devel- oped model and numerical analysis. By compare of the results of the numerical simulation and experimental study, it is showed that the output of sensing signal of the sensor is associated with the amplitude and the frequency of the actuating voltage as well as the dimension and boundary condition of embedded PZT patch. In the PZT sensor model, from the piezoelectric equations and equations of the joint solution, you can quickly get PZT sensor signal, by comparing experimental evidence to establish the correctness of the mechanical model.