Differential pressure method for measuring water holdup of oil–water two-phase flow with low velocity and high water-cut

Abstract

This paper is devoted to measuring water holdup of oil–water two-phase flow with low velocity and high water-cut through differential pressure method. At first, we carry out vertical upward oil–water two-phase flow experiment in a 20mm inner diameter pipe to obtain the response of differential pressure sensor, and use Vertical Multiple Electrode Array conductance sensor (VMEA) as well as Adaptive Optimal Kernel Time–Frequency Representation (AOK TFR) algorithm to identify three different flow patterns, i.e., dispersed oil-in-water slug flow (D OS/W), dispersed oil-in-water flow (D O/W) and very fine dispersed oil-in-water flow (VFD O/W). Then the water holdup is extracted from the differential pressure sensor response by calculating frictional gradient loss, and the water holdup measured is compared with the set value by using the method of quick closing valve. Finally, we using drift-flux model predict the individual phase superficial velocities based on the flow pattern classification and water holdup. The research results show that differential pressure method proves to be an effective approach to investigate flow characteristics in oil–water two-phase flow with low velocity and high water-cut.