An experimental study of two-phase flow in slightly inclined pipes—II. Liquid holdup and pressure drop

Abstract

A series of oil—air two-phase flow experiments were conducted with a 25 m long acrylic pipe (Part I). Pressure drop and liquid holdup were found to be flow pattern dependent. Intermittent flow was the dominant flow regime in upward flow while stratified flow dominated in downward inclined pipes. For Almost all parameters in this model were calculated from first principles and an interfacial shear term was added for the gas film. This model yields excellent results even for the transition region between the intermittent and truly annular flow designated as “proto”-slug flow. A separated model has been proposed for stratified flow and homogeneous models for dispersed bubble and annular flow for predicting pressure drop and liquid holdup in inclined pipes. The results show good agreement with the experimental data.