Monte Carlo uncertainty quantification method of pneumatic measurement tube frequency response

Abstract

The pneumatic tube plays a critical role in the frequency response of the pressure measurement system, which also greatly affects the accuracy of the measurement data. This paper applied the Monte Carlo uncertainty qualification method to the pressure measurement tube system frequency response and studied the effects of four parameters, including tube length, radius, temperature, and source pressure, on uncertainty characteristics for a given tube system configuration. The reported results show the technique's applicability and flexibility and the limitations of GUM. It is found that the frequency response and corresponding uncertainty are not directly related to frequency but are closely related to the natural frequencies. Comparative experimental results show that the longer tube significantly reduces the system's natural frequencies and intensifies the phase lag. In addition, larger tube radius and source pressure result in larger amplitude response peaks. Closed to the natural frequencies, with the increase of the parameter, the uncertainties of frequency response value and the corresponding variation range increase for tube radius and source pressure while decreasing for temperature and tube length.