Author(s)

S. Vestøl, A. S. Kumara, M. C. Melaaen

Abstract

This paper presents detailed measurements on gas–liquid flows in horizontal and slightly inclined pipes. The mixture velocities, liquid fractions and pipe inclinations used in the experiments are in a range that is commonly used in transportation of unprocessed gas in offshore oil and gas industry. The experimental activities were performed using the multiphase flow loop at Telemark University College, Porsgrunn, Norway. The experiments were conducted in a 15 m long, 56 mm diameter, inclinable steel pipe using Exxsol D60 oil (density 793 kg/m3 and viscosity 1.3 mPa·s), water (density 999 kg/m3 and viscosity 0.89 mPa·s) and air (density 1.22 kg/m3 and viscosity 0.018 mPa·s) as test fluids. Mixture velocities of 5, 10 and 15 m/s, liquid fractions of 0.0010, 0.0025, 0.0050, 0.0075 and 0.0100 and pipe inclinations of -5°, -1°, 0, +1° and +5° from horizontal were investigated. The time-averaged crosssectional distributions of gas and liquid phases were measured using a singlebeam gamma densitometer. The characterization of flow patterns and identification of their boundaries were performed using high-speed videos, still pictures and live observations. Seven different flow patterns were identified for gas liquid flow in horizontal and slightly inclined pipes. The pressure drop and liquid hold-up measurements were also reported.

Keywords

gas–liquid flow, mixture velocity, hold-up, pressure drop, horizontal flow, inclined flow, liquid fraction, flow pattern, gamma densitometer