压电加速度计在不同安装方式下的响应分析

Response Analysis of Piezoelectric Accelerometer under Different Installation Methods

摘要:

在固体火箭发动机力学试验中，不同的安装方式会对压电加速度计的响应产生影响，从而会影响最终的实验结果。通过建立力学理论模型,分析得出压电加速度计的安装谐振频率与加速度计和试件间的连接刚度成正比关系。通过设立多组对比实验，比较不同安装方式下的压电加速度计灵敏度幅值、相对偏差随频率和加速度的变化关系，得出不同安装方式下压电加速度计的适用范围。502胶水的安装方式可以同时满足精度要求很高、试验时间较长、试验频率范围广的要求，而胶木座、磁座、磁座+502、双面胶的安装方式均有不同的使用限制。同时，通过对比180°同轴安装和直接安装时的压电加速度计安装传递系数随频率的变化关系，进一步验证直接安装可以避免多级传递带来的偏差。

Abstract:

In the mechanical test of solid rocket motor, different installation methods will affect the response of piezoelectric accelerometer, which will affect the final experimental results. Through the establishment of the mechanical theoretical model, it is found that the resonant frequency of the piezoelectric accelerometer installation is directly proportional to the connection stiffness between the accelerometer and the test piece. Compare the sensitivity amplitudes and relative deviation of piezoelectric accelerometer under different installation methods by setting up multiple groups of comparative experiments. The installation method of 502 glue can meet the requirements of high precision, long test time and wide test frequency range at the same time, while the installation methods of bakelite base, magnetic base, magnetic base + 502 and double-sided glue have different use restrictions. And the applicable range of piezoelectric accelerometer under different installation methods is obtained. At the same time, by comparing the transmission coefficient of piezoelectric accelerometers installed in 180°coaxial installation and direct installation with the change of frequency, it is further verified that direct installation can avoid the deviation caused by multi-level transmission.