Characterization of Oil/Water Flows in Inclined Pipes

Abstract

Oil/water flow is a common occurrence during production and transportation of petroleum fluids through pipes. Understanding of oil/water pipe flow behaviors is crucial to many applications including design and operation of flow lines and wells, separation, and interpretation of production logs. In this study, the oil/water pipe flow was experimentally investigated for different inclination angles (0 o , ±1 o , ±2 o and -5 o ). A total of 324 tests were conducted in a 0.0508-m (2-in.) ID 21.1-m (69.6-ft) long test section using tap water and mineral oil with superficial velocities ranging from 0.025 to 1.75 m/s. The experimental results include observations of flow patterns and phase distributions, and measurements of water holdups and pressure gradients. A high-speed video system was used to observe the mixing status between oil and water and to determine the flow patterns at various flow conditions. Quick closing valves were used to measure the phase holdups and to demonstrate the slippage between oil and water with the water cut to water holdup ratio. The experimental results of flow pattern transitions, water holdups, and pressure gradients are compared against predictions of the Zhang and Sarica (2006) model. The model performance is analyzed based on the experimental observations and the modeling considerations. Recommendations are presented for future model improvement.

Experiments and Model Assessment on High-Viscosity Oil/Water Inclined Pipe Flows

“…Several experimental studies of oil/water pipe flow have been conducted including Flores (1997), Angeli et al (1998), Alkaya (2000), Lum et al (2004) and Atmaca (2007). These studies cover a wide range of water cuts from 0 to 100% and mixture velocities up to 4 m/s.…”

“…The model is for horizontal and near horizontal flows and can predict flow patterns, pressure gradient and volumetric holdup. The model was validated using experimental data from the studies of Atmaca (2007), Abduvayt (2006), Alkaya (2000) and Trallero (1995). McKibben et al (2000) investigated heavy oil/water flows in horizontal wells at low velocities.…”

Characteristics of water holdup for oil and water mixture flows in horizontal, vertical, and inclined pipes

“…As is shown, the developed drift-flux model Figure 13. Effects of the flow direction on water holdup at constant superficial velocity in the small inclined flow from À28 to 28 (data from Atmaca et al [5] ). Figure 14.…”

“…Effects of the mixture flow velocity on the slip velocity ratio and water holdup at a constant input water fraction (b W ¼ 0.5) in the small inclined flows from À58 to 58 (data from Kumar et al [6] ). Abduvayt et al [4] 8.1 14.0 20.5 116 Atmaca et al [5] 3.8 11.6 15.8 83 Flores et al [1] À8.0 8.3 10.0 89 Kumara et al [6] 1.6 15.5 31.5 22 Lum et al [7,8] À0.3 10.3 22.0 121 Mukherjee et al [2] À2.6 8.0 15.1 228 Oddie et al [23] À1.6 6.3 7.1 8 Rodriguez and Oliemans [9] 14.1 19.6 24.1 19 Rodriguez and Baldani [24] 36.2 38.7 25.1 17 Vigneaux et al [3] À11.0 11.1 6. 5 25 can give a reasonable performance with 98 % of the data having an average absolute error less than 20 %.…”

Mechanistic Prediction of Oil-Water, Two-Phase Flow in Horizontal or Near-Horizontal Pipes for a Wide Range of Oil Viscosities

“…Flow regime maps are usually presented in the space of superficial oil velocity and superficial water velocity. Models have been proposed to predict the transition from one flow regime to another by several researchers, including Brauner (1991), Brauner and Moalem Maron (1992), Brauner (2003), Zhang et al (2003), and Atmaca et al (2009).…”