Dispersed oil–water–gas flow through a horizontal pipe

Abstract

An experimental study of three‐phase dispersed flow in a horizontal pipe has been carried out. The pressure drop over the pipe strongly increases with increasing bubble and drop volume fraction. Because of the presence of drops the transition from dispersed bubble flow to elongated bubble flow occurs at a lower gas volume fraction. The gas bubbles have no significant influence on the phase inversion process. However, phase inversion has a strong effect on the gas bubbles. Just before inversion large bubbles are present and the flow pattern is elongated bubble flow. During the inversion process the bubbles break‐up quickly and as the dispersed drop volume fraction after inversion is much lower than before inversion, a dispersed bubble flow is present after inversion. (When inversion is postponed to high dispersed phase fractions, the volume fraction of the dispersed phase can be as high as 0.9 before inversion and as low as 0.1 after inversion.) © 2009 American Institute of Chemical Engineers AIChE J, 2009

Characterization of liquid‐liquid flows in horizontal pipes

“…When the oil is more viscous, the water phase needs higher turbulent kinetic energy to disperse the oil phase thus the critical water volume fraction to form stable Do/w increases. It is worth remarking that apart from the influences of oil viscosity and mixture velocity, other parameters such as the interfacial tension, phase volume fraction increase method (continuously or discontinuously) and transition direction (from oil‐continuous to water‐continuous or the opposite) can also affect the transition from Dw/o to Do/w . It is hardly possible to include all the influences of different parameters on the inversion in one map.…”

“…In the petroleum industry, oil and water are frequently transported together in wells and pipelines. A lot of studies on particular liquid‐liquid flow systems, e.g., low‐viscosity oil‐water flow, high‐viscosity oil‐water flow, specific flow regimes such as stratified flow, dispersed flow and core annular flow, have been reported in the literature. These studies greatly contribute to our understanding of liquid‐liquid flows.…”

Oil–gas–water three-phase upward flow through a vertical pipe: Influence of gas injection on the pressure gradient

“…6 presents the measured friction factors in three-phase flow as a function of the in situ gas fraction for four different values of superficial gas velocity. As can be seen the friction factor for the three-phase flow is quickly increasing with superficial gas velocity up to the value of 0.85 m/s, at which point the mixture flow show an intermittent flow pattern and a very strong increase of the friction factor occurs (Piela et al, 2009). This means that the injection of gas into an oil-water flow increases dramatically the friction term of the pressure gradient in the Eq.…”

Sensor‐based flow pattern detection—gas–liquid–liquid upflow through a vertical pipe

“…A survey of the past literature reveals that the most commonly used optical technique in two‐ and three‐phase flows is the optical fiber probe (Piela et al, Fordham et al). It is based on either Fresnel reflectivity or total internal reflection of light emitted from the fiber tip and is a measure of the refractive index contrast.…”

“…For three‐phase gas–liquid–liquid flow, the majority of the studies (Table ) have used visual and photographic observations to identify flow patterns. The only exceptions are Wang et al 4 who have adopted the conductivity probe technique and Piela et al who have investigated three‐phase dispersed flow in a horizontal pipe from signals obtained from a single tip optical fiber probe.…”