Experimental investigation of gas-oil two-phase flow using electrical capacitance tomography

An 8-electrode electrical capacitance tomography (ECT) sensor located at the venturi throat on a vertical pipeline is used to investigate the flow regime of gas-oil two-phase flow. The experiment was carried out with the gas volume fraction (GVF) varies from 10% to 90% at different flow rates of oil. Slug flow appears at a low GVF. While with a high GVF, a clear annular flow will be formed. For different flow rates of oil, the flow regime at the same GVF point could be different because of the flow rate of gas (or superficial velocity of gas). A method independent of flow regime is developed to calculate the phase fraction of gas-oil two-phase flows. The absolute error can be within ±10%, illustrating that this method is effective.