Experimental Study of Flow Patterns and Pressure Drop Reduction in Pipes of Oil-Water Flow

Abstract

Heavy oils cannot easily flow through pipes due to their high viscosity. Technologies to enhance the mobility of heavy oils are required in oil production and transportation. Transportation of heavy oil by lubricated technique looks an attractive method for saving pumping power. In this study, the effect of varying mean injection velocity of water on the flow structure and the pressure gradient of the two-phase flow was studied experimentally by using heavy oil (viscosity = 750 mPa.s at 40 °C) flow in a horizontal pipe of 29 mm inner diameter and 3.66 m long test section. With the help of photography, six different flow patterns were identified and the flow pattern maps were constructed for each case. The pressure drop reduction factor was introduced to characterize the oil-water two-phase flow. From the results, the pressure drop reduction factor increases with increasing the amount of oil transported. The water input ratio decreases with increasing the oil flow rate (in the direction of annular flow observation). The experimental data for pressure drop was compared with the analytical solution of Arney model. From the comparison, the deviation between the experimental data and the predication of the analytical model is less than 20%.