Experimental Study On Oil/water Two Phase Flow In A Horizontal Pipe Of Small Diameter

At present, the horizontal well is playing an increasing important role in oilfield development, for it can enhance the oil recovery and cut down the cost of oilfield development. By the role of gravitation, distributions of dispersed phase and flow velocity are no longer symmetry in horizontal wells or incline wells, which is different from vertical wells, and the flow pattern becomes even more complex, that will impact the measurement and logging explanations. Therefore, it is essential to research the flow rules of fluids in horizontal wells.In this paper, a set of experiment devices which can avoid the leaking of packing umbrella and the disturbance of flow pattern was designed to simulate the oil/water two-phase flow. Dynamic response experiments of impedance sensor and turbine sensor were carried out at 5 angles which are near horizontal, and the flow rules are shot through the plexiglass pipe by a CCD camera.Experiment results have shown that the low limit of measurement of the impedance sensor in horizontal wells will be lower than that of vertical wells, and the relative response of the sensor is affected by well inclination and phase slippage. Research results on Maxwell model in near horizontal wells has shown that the water holdup can be calculated through Maxwell model. The response of turbine sensor will be less affected by well inclination, but much affected by water cut. Analysis results of the flow pattern have shown that the flow pattern mainly includes stratified flow and dispersed flow, and the water holdup of stratified flow will be much affected by well inclinations.Water cut has been predicted through the draft model and the slippage model. The explanation results have shown that both two models can be used in near horizontal wells and the prediction effect of the slippage model in water cut is better than that of the draft model.The Ansys software was used for simulating the 3D electric field distributions of the impedance sensor in stratified flow. The results have shown a linear relationship between the relative response and the water holdup. Static researches on the impedance sensor in stratified condition were carried out through the"Height"method and the experiment results agreed with the simulation results.