PREDICTION OF LIQUID-LEVEL DISTRIBUTION IN HORIZONTAL GAS-LIQUID STRATIFIED FLOWS WITH INTERFACIAL LEVEL GRADIENT

A one-dimensional momentum equation has been derived based on a two-fl uid model and used to predict the axial distribution of liquid level o r void fraction in steady, cocurrent, gas-liquid stratified flows in h orizontal circular pipes and rectangular channels. The equation is car efully formulated to incorporate the effect of interfacial level gradi ent. Two different critical liquid levels are found from the momentum equation and are adopted as a boundary condition to calculate the liqu id level or void fraction distribution upstream of the channel exit. T he predicted void fraction distributions are compared with the experim ental data obtained in a rectangular channel in this work and other da ta reported for large-diameter pipes. Good agreement is shown for air- kerosene, air-water and stream-water stratified flows with a smooth ga s-liquid interface.