The characteristics of the pressure gradient air-water stratified two-phase flow in horizontal pipes

Abstract

The co-current air-water two-phase stratified flow is desired to occur in the application of pipelines system, such as natural gas gathering, long distance pipelines, and transmission pipelines, because this flow characteristics offers some advantages related to the safety factor of operational condition. The characteristics of pressure drop in stratified flow is considered as one of an important factor in the capital and operation costs for the simultaneous transportation of gas and liquid in various industries. The main objective of this study is to examine the effect of gas and liquid superficial velocities, and pipes diameter on the characteristics of pressure drop air-water two-phase stratified flow. Experiment has been conducted in 26 and 16 mm i.d. acrylic horizontal pipe with length 9.5 m. Air-water flow was recorded 190 D from the inlet using high speed video camera, and pressure difference was measured between 180 D and 210 D from the inlet using validyne pressure transducer. The common parameters such as visualization, pressure gradient signal in time series, probability density function (PDF), and mean of pressure gradient was analyzed. As a result the effect of gas and liquid superficial velocity, and pipes diameter on the characteristics of pressure gradient can be understood.