LIQUID VELOCITY MEASUREMENT IN VERTICAL SLUG FLOW

摘要

Experimental studies of vertical slug flow were carried out with an electromagnetic flowmeter in an air-water two-phase experimental loop. Basic principles of the instrument in vertical slug flow measurements are discussed. For the first time, the area-averaged liquid velocity of slug flow was revealed by the electromagnetic flowmeter. Time series of the liquid velocity were separated into two parts corresponding to the Taylor bubble and the liquid slug. Characteristics of slug flow, such as the area-averaged liquid velocity and the liquid film velocity of the Taylor bubble tail, etc., were obtained. It is realized that the void fraction of the liquid slug is determined by the turbulent intensity due to the relative liquid motion between the Taylor bubble tail region and its wake region. A correlation of the void fraction of the liquid slug was developed based on experimental results obtained from a test section with 50.8mm i.d.