The objective of this project is to measure and observe high-viscosityoil/water/gas three-phase flows in horizontal and upward vertical pipes, andcompare the experimental results with existing models to identify the gaps. Inthis study, oil with viscosities between 0.15 and 0.57 Pa•s (150 and 570 cP)corresponding to temperatures from 37.8 to 15.6 °C (100 to 60 °F), filtered tapwater and natural gas at 2.59 MPa (375 psig) pressure are used as the threephases. Superficial oil and water velocities range from 0.1 to 1.0 m/s andsuperficial gas velocity varies from 1.0 to 5.0 m/s. The internal diameter ofthe pipe is 5.25-cm (2.067 in). The experimental measurements include pressuregradient and liquid holdup. The flow pattern and slug characteristics areobserved and the images are recorded with a high speed video camera systemthrough a high pressure sapphire window. The experimental results are comparedwith the predictions of Zhang and Sarica (2006) unified model, and thediscrepancies are identified.
Heavy oil, extra heavy oil together with bitumen constitutes about 70% of theworld's total oil reserve. They are discovered and produced all around theworld and have become one of the most important future hydrocarbon resourceswith ever increasing world energy demand and depletion of conventional oils. However, the high viscosity of heavy oils poses many challenges for itsproduction and transportation.
Three-phase flow of oil, water and gas is of particular importance for the oilindustry. It frequently occurs in wells, risers and flowlines before reachingthe downstream processing facilities. The water can be introduced either due tothe connate water condensation or water steam injection for enhanced oilrecovery at the later stage of production. Understanding of the three-phaseflow phenomena is necessary in order to better design the production andtransportation systems. Most of the previous experimental researches, model andcorrelation developments were conducted using low-viscosity conventional oilsor other liquids. Açikgöz et al. (1992) carried out the first experimentalinvestigation of three-phase flow patterns in horizontal pipes. Pan et al.(1995) performed similar horizontal experiments. The tests were conducted at 5bar pressure and in a 38.0-m long horizontal, 7.62-cm ID pipe. Woods et al.(1998) reported oil/water/air upward vertical flow in a 2.52-cm ID Perspex pipewith a 1.8-m test section. Nine flow patterns were identified based onvisual/video observations and pressure techniques. Langsholt et al. (2001)studied oil/water/gas flows in steeply inclined pipes. Hewitt (2005) studiedthree-phase oil/water/air flows in a 38.0-m long, 7.62-cm ID stainless steelpipes. Keskin et al. (2007) proposed a two step classification method foroil/water/gas three-phase flow patterns. 12 flow patterns were identified forhorizontal and slightly inclined flows.
