Design and performance of a six-electrode conductance probe for measuring the water fraction in oil-in-water pipe flow

The performance of ring-shape electrodes for measuring the conductance of oil-in-water mixtures in pipes was studied theoretically and experimentally. In particular the work is aimed at optimizing the probe geometry in order to decrease the axial current leakage and improve the measuring precision of water fraction under oil-well logging application. Starting from the basic four-electrode probe including two exciting and two measuring rings, a new six-electrode probe characterized by adding two guarding rings to be found, the distance and width of guarding electrodes were optimized theoretically. The experiment was performed with reference to annular, stratified and bubble phase distributions and the results were compared with available theoretical models. The analysis demonstrates the response of new six-electrode probe is accurate and reliability, the measuring precision is enhanced.