Investigation of vibration effect on dynamic calibration of pressure sensors based on shock tube system

Abstract

This paper devotes to investigate the influence of vibration on dynamic calibration of pressure sensors based on shock tube system. Two sensors with different types are separately calibrated under the same step pressure to distinguish the individual sensor’s dependent effect. To excavate how the sensor’s dynamic characteristics fluctuate under different vibration cases, support mounts and buffer rings of different materials are used in the experimental shock tube system. Vibrations from two main sources are expounded in detail and detected by an acceleration sensor installed near the pressure sensors. Based on the outputs of sensors, the influences of vibration on the repeatability, stability and dynamic characteristics of pressure sensors are analyzed qualitatively and quantitatively. Furthermore, a weighted scoring method based on the relative standard deviation of the calibration parameters is proposed to comprehensively assess the vibration effect on dynamic calibration results of pressure sensors. The experimental results show that the influence of vibration from the rupture of diaphragm on dynamic calibration can be avoided suitably by using the mount with high damping material or a shock tube with long driven section. The vibration from the instantaneous impact of shock wave has slight influence on the repeatability, rise time and resonant frequency, and significant influence on the stability, settling time, overshoot and uncertainty in working band of pressure sensors. Based on the weighted scores under different vibration cases, the combination of steel mount and aluminum ring produces the most reliable calibration result. These findings are also verified by another group of calibration experiments with a smaller amplitude of step pressure.