Slug Flow Transition in Horizontal Gas-Liquid Flow

Abstract

We investigated a horizontal two-phase flow transition from separated flow to slug flow without a phase change. A transition model is presented in this paper, based on the experimental results obtained in the air-water system. The model is derived from the growth condition of a wave on a stratified water layer. It agrees reasonably well with Mandhane's map of flow patterns. If disturbances enter the system, the slug flow transition is sometimes enhanced. To examine this transition enhancement, a test tube was attached to a water tank with a weir to regulate the initial water depth in the tube. When a water slug flows out of the tube, a bore goes upstream in the tube, and occasionally causes formation of a next slug. The theoretical model is used to predict the conditions of continual slug formation. The hydrodynamic behavior of slug flow is also examined.