Water content measurement by radio frequency method under the condition of oil-water two-phase spiral flow

At present, most oilfields in China have entered the late stage of oil recovery, and the water content of crude oil has increased significantly, which has brought new challenges to the measurement of water content. For the problem of real-time measurement of water content of crude oil, this paper proposes a new method of water content measurement by radio frequency method under oil-water two-phase spiral flow. First, the oil-water two-phase flow is adjusted to a spiral flow state by a cyclone, then the radio frequency signal emitted by the antenna arranged concentrically in the tube under the spiral flow state is measured, and finally the water content ratio is achieved by establishing a relationship model between the water content and the RF signal measuring. This method can eliminate the influence of the oil-water two-phase flow pattern on the measurement results and widen the measurement range of the water content. The measurement model was statically calibrated, dynamically verified, and optimized through laboratory experiments. The experimental results show that when the inlet oil-water two-phase mixing flow rate is 0.60-1.20 m/s and the volumetric water content is higher than 43.81%, the error of the oil-water two-phase measurement using this method is within 6.29%.