Abstract
Within the field of process measurements, there is need of an effective method for accurately measuring unsteady flow rates independent of the state of flow or the characteristics of fluid. In general, an air chamber is often installed as an accumulator in a pipeline to smooth the unsteady flow. In this paper, we propose a new method that utilizes an air chamber for measuring the unsteady flow rate. Volume change of the air chamber is obtained from the measured pressure and the estimated temperature. The estimated temperature is calculated numerically by simultaneously solving the equation of state and the one dimensional approximated heat transfer equation. To evaluate this method, a simple experimental model was employed, and the measured flow rate was compared to the estimated one. Good agreement was achieved between the measured and the estimated unsteady flow rate, and then the accuracy of this method was discussed.
