Two-phase (gas—liquid) flow phenomena—I Pressure drop and hold-up for two-phase flow in vertical tubes

Abstract

An attempt has been made to develop a theory for two-phase flow in a vertical tube when the liquid flow is annular. Published data on liquid hold-up and pressure gradient have been examined in the light of this theory together with original data obtained on air-water mixtures in a 1 2 in. diameter glass tube. Predictions of the liquid film thickness were found to be accurate to ± 15 per cent. The theory also predicted the flow conditions under which annular flow gave way to slug flow. An approach has been made to an empirical correlation of friction factors at the gas-liquid interface.