Frictional factor correlation for laminar high-viscosity oil/gas flow in horizontal pipes

Pressure drop prediction of high-viscosity oil/gas flow is an important issue in several industries, and it has a great interest for many researchers. This paper presents a simplified correlation for two-phase high-viscosity oil/gas flow friction factor in horizontal pipes. The developed friction factor is a sole function of Reynolds number on the basis of the mixture velocity and liquid properties. The recently developed friction factor correlation for laminar and turbulent gas/liquid flow is not suitable for the high-viscosity liquid/gas flow for which Reynolds number is less than 2,000. The validation of the proposed correlation against experimental data and the newly developed correlation showed accurate results for the two-phase friction factor for the cases matching gas/heavy oil flow with liquid holdup greater than 0.5 and mixture Reynolds number on the basis of liquid properties less than 2,000. The proposed correlation accuracy is better than the generalized correlation developed for all viscosities and Reynolds numbers and liquid holdup greater than 0.5. The less the Reynolds number, the more accurate the results.