Pressure drop measurements of oil (D80)-water flow in 6” horizontal and inclined annulus pipe

The flow of two immiscible liquids (such as oil and water) in pipes is a challenging subject that is rich in physics and practical applications. It is often encountered in many oil and chemical industries. The pressure gradient and flow patterns of immiscible liquids are still subject of immense research interest. This is partly because fluids with different properties exhibit different flow behaviors in different pipe’s configurations under different operating conditions. More importantly, oil-water annular flow (oil surrounded by water) is a common occurrence in oil upstream petroleum industry and is generally used for the lubricated transportation of highly viscous oil. However, despite their importance, behavior of such flows has not been explored to an appreciable extent. The present study reports pressure drop measurements of oil (D80)-water annular two-phase flow in a horizontal and inclined 6 inch diameter stainless steel pipe at different flow conditions. Experiments were carried out for different inclination angles including; 0°, 40°, 60° 90° and for different water cut (WC) ratios. Water cut ratios were varied from 0 to 100% in steps of 20%. Inlet oil-water flow rates were varied from 2000 to 12000 barrels-per-day (BPD). For a given flow rate (for all angles) the frictional pressure drop has been found to increases from WC = 0 to WC 40%. Further increase in WC, friction pressure drop has been found to decrease. In general, frictional pressure drop increases with flow rate and water cut and the effect of angle was not appreciable. The behavior of total pressure was asymptotic with increase in flow rate. Also the behavior of total pressure was linear with respect to WC up to 80%.