The Influence Of Water Cut On Flow Pattern And Pressure Drop Of Gas Liquid Multiphase Transportation Pipeline

In the oil and gas industry,gas-liquid mixing pipeline is widely used in order to effectively reduce production cost and reduce energy consumption.However,with the passage of time,many major oil fields in the east of our country have slowly entered into the later stage of development,and the development direction of petroleum resources have slowly turned to the ocean,desert,beach,polar regions and so on,thus leading to different water cut of oil products.At present,when most scholars study gas-liquid two phase flow,they rarely consider the influence of different water cut on the flow pattern and pressure drop.Thus it is difficult to predict real flow characteristics of oil field products,so we need to research the influence of different water cut on the flow pattern and pressure drop of gas-liquid mixing pipeline.Using the white oil,water and air as oil-gas-water three phase medium,this paper does the gas-liquid two phase flow experiments of different water cut(0%?30%?60%?90%)in a horizontal pipe of Yangtze University 's multiphase flow experiment platform.Based on the experimental phenomena and experimental data,the flow pattern map of oil-gas-water three phase flow under different water cut is established,and the influence of water cut on the flow pattern's boundary and pressure drop of the three-phase flow is analyzed.By analyzing the mutation of pressure drop,the anti-phase phenomenon of oil and water mixture is discussed,and the anti-phase point is 40% water fraction.In order to study the influence of water cut on the three-phase flow pattern,two kinds of separation methods are adopted for the three phase flow patterns of oil,gas and water,and the mechanisms of transformation in the two kinds of cases are analyzed.In addition,two-phase flow pressure drop models of high water cut are established.Three classic kinds of pressure drop algorithms--the Baker,Mandhane and Beggs-Brill are used for the calculation of pressure drop.By comparing the calculated values of three kinds of models and the measured values of oil-gas-water three phase pipeline,it is found that the errors of Mandhane and Beggs-Brill models are bigger,while the errors of Baker model are smaller.The Baker pressure drop model is corrected by using the measured values of the three phase gathering and transportation pipelines.