| The daqing oilfield and most domestic continental sediments of oilfield production wells have the characteristics of low production and producing multi-layer. Most of oil fields have got into a high water cut stage, and now a large number of oil wells produce nature gas, which cause oil, gas and water three-phase fluid distribute in oil wells. With the gas phase added, the flow patterns of down hole fluid are various, which makes it difficult to production profile well logging. According the needs three-phase flow pattern and tool responses regulations of flowrate and water cut measurement in three-phase flow, the research was proposed in the paper.A special experiment facility of small diameter three-phase flow was designed. The experiments adopted widely used impedance water holdup meter, turbine flowmeter and differential pressure density meter. And dynamic experiment study of these meters were conducted on the facility. A transparent pipe was designed on the facility. The flow pattern and flow state of fluid flowing through the transparent pipe were recorded by high speed camera. By now the design of the special experiment facility was already completed, and now is in the stage of manufacture.The research of three-phase flow is a long-term and arduous task. The research of gas/liquid two phase flow is the key to oil/gas/water three-phase flow. In the paper, the study of tool responses of spinner flowmeter, cross-correlation flowmeter and conductance water holdup meter in gas/water two-phase flow was carried out. Many important results were obtained through the experiment.The experiment of turbine flow meter is carried out on the simulation multi-phase flow experiment facility under the condition of gas-water two phase flow. The turbine flowmeter has different response regulations at low flowrate and high flowrate. When the water flowrate is above 10m3/d and the gas flowrate is constant, the response of turbine flowrate is liner to the water flowrate. Further more, along with the increasing of gas flowrate, the K value of turbine flowmeter increases. Under the low fluid volume (<10m3/d), the response of turbine flowrate is more sensitive to gas flowrate, when gas flowrate is more than 20m3/d, the turbine flowmeter is not sensitive to water flowrate.The experiment results of cross-correlation conductance flowmeter in gas/water two phase flow have shown that the cross-correlation conductance flowmeter can be suitable to determine the gas/water total flowrate with the gas flowrate from 3 to15m3/d and the total flowrate above 20m3/d. When the total flowrate is lower than 20m3/d, the measurement results of correlation flowmeter are greatly affected by gas slippage. The lower the flowrate is, the more obvious the gas slippage effect is.The impedance water cut meter has a good resolution in the gas/water two phase flow. With the flowrate increasing, the resolution will be better. Gas slippage effect will become more obvious along with the flowrate increasing. Water cut response has been predicted through the draft model. The explanation results have shown that the draft model can be used for water cut prediction in high flowrate.In this paper, the flow pattern of oil /gas/ water three phase flows have been discussed, The FLUENT software was used for simulating the flow patterns of oil/gas/water three phase flows and gas/water two phase flow in small diameter vertical pipe, the results can provide a reference for the future research.
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