Research on unsteady flow measurement standard device based on active piston

In this paper, an unsteady flow measurement standard device is studied and designed. The device can be used to measure the flow rate of any liquid medium. First, through comparative analysis of the design scheme of the unsteady flow measurement standard device, the structure of the active piston type is determined, and the schematic diagram is designed. According to the schematic diagram, the mathematical model of the device based on the active piston is established, and the uncertainty of the device is evaluated. Second, the hardware control system is designed and built according to the uncertainty evaluation results. Then, the upper computer operating system of the device is constructed, and a highly integrated human-computer interaction data acquisition and control system is established. Finally, the measurement performance of the device is verified by comparing the set value with the measured value of flow rate, and the uncertainty of the device is analyzed. The combined standard uncertainty can meet the expected value of 0.5%.