Measurement of Interface Level, Holdup, Pulsation Frequency, and Amplitude in a Pulsed Column by Air Purge

Abstract

The air purge is an old method. However, it is very simple and suitable for the nuclear industry where the simple, robust instruments are required. In the present work, the long-distance and online measurement of the pulsed column parameters was achieved by a simple insertion of three purge probes. The specially constructed purge probes were installed in the pulsed column, and two differential pressure response curves were obtained on a computer. The two curves give information on the two-phase interface level, holdup, and pulsation intensity. The measuring accuracy for the two-phase interface level is within ±5 mm. The relative measuring deviations are within ±2% for pulsation frequency and within ±5% for holdup. One response curve reflects the sinusoidal pulsation wave, and a parameter S was derived from the area of the sinusoidal waveform. A good linear relationship between apparent pulsation amplitude and the parameter S was found. The dependency of the real pulsation amplitude on the apparent pulsation amplitude and frequency has been experimentally determined. Thus, the real pulsation amplitude can also be measured by direct air purge.