Area‐alterable liquid electrode capacitance sensor for water holdup measurement in oil–water two‐phase flow

Abstract

Oil–water two‐phase flow exists widely in the process of petroleum industry. The water holdup is an important parameter but difficult to measure. In this paper, we develop an area‐alterable liquid electrode capacitance sensor for water holdup measurement in oil–water two‐phase flow. The capacitance sensor has a relatively high measurement sensitivity and a good linearity in the full range of the water holdup, from 0% to 100%. Meanwhile, a firing technology of insulating layer is presented to guarantee the characteristics of the capacitance sensor with high temperature resistance, corrosion resistance, and non‐stickiness. The static performance of the capacitance sensor is validated theoretically and experimentally. Vertical upward oil–water two‐phase flow experiments indicate that the developed capacitance sensor has good performance for water holdup measurement with average relative error of 10% in the full range of the water holdup. Based on the output signal of the sensor, the information of flow structure can be also estimated in different flow patterns.