Numerical Study of Pipework Arrangement Effects on Flow Rate Fed into Calibrated Flowmeter

摘要

In this paper, a piezoelectrically-actuated flow excitation approach is presented for producing short rise- time flow rate changes, needed by flowmeter dynamic calibration. A double nozzle-flapper valve (NFV) is adopted as excitation flow generator. A piezoelectric stack commercially available drives the flapper. The working principle of the calibration system is put forward and three-dimensional model of the whole pipework is built. Moreover, the pipework arrangement effects on system performance is studied including length of the control chamber, volume of the nozzle reserving chamber and symmetry degree of Pipework. It is shown that the pipework arrangement has remarkable influence on the dynamic calibration process of the flowmeter and the measurement accuracy of the whole system.