Research Of Three-Phase Measuring Technology At The Mouth Of Oil Well

On-line measurement of three-phase flow of the oil, gas and water mixture is significantly valuable to the exploitation of oil fields, especially located on the sea or far from the city. But it is very difficult to develop multiphase flowmeters due to the complexity of flow regimes and inconstancy of flow composition at flowing conditions, thus far there are few practicable multiphase flowmeters available.A research of the measurement of multiphase flow is shown in this paper. On based of the domestic and international related documents, several measuring methods of multiphase and the existing multiphase flowmeters are summarized and compared. By analyzing the basic principle, application, merits and shortcomings of existing methods and flowmeters, it describes a new method that can measure the multiphase flow by using segregator, water analyzer, densimeter and orifice flowmeter. And a method based on computational fluid dynamics software is advanced at the same time.Three T-junctions are used to separate multiphase flow; Coriolis mass flowmeter is used to measure the density and composition of multiphase flow; the relation between difference pressure signal and flow mass, difference pressure signal and velocity through the orifice flowmeter is analyzed and transmitted; Then, a slotted orifice is designed; At last, much experiments are made.Based on the computational fluid dynamics technology, the Computational Fluid Dynamics technology, ICEM CFD and CFX 11.0 are used to simulate flow behavior across the standard orifice. The pressure, velocity streamline in the orifice flowmeter and the pressure distribution of standard orifice in the centerline are given.The equipment based on this method has many advantages, such as the small volume, the compact system, the expand measuring range, easy to repair, no-radioactivity, low cost and so on. The measuring system is fully respect the direction of multiphase flowmeter in the future. The method is useful to the measurement of flow by use of the Computational Fluid Dynamics softwares, and as well is instructive and available to the development of orifice flowmeter.