同井泵抽系统油水分离效率与泵功图仿真模型研究

针对高含水油田所带来的开采问题,基于所建立的数学模型,分别计算了注入泵、采出泵进入口气液比,油、气的分离效率,得出气液比、分离效率之间的影响关系。综合考虑柱塞的运动规律、泵筒内流体的可压缩性,建立了泵筒内流体流动的连续流方程。根据连续流方程,建立了柱塞运动规律、泵筒内液体压力与泵筒气体体积之间相互关系的数学模型,从而建立了泵筒内液体瞬时压力与泵示功图的仿真模型。仿真实例表明:当生产燃油比GOR增大时,泵筒内的气体增多,注、采双泵游动阀与固定阀开启时间滞后;当生产燃油比GOR增大到一定程度时,注、采双泵泵腔内的气体体积足够大,不仅会导致上冲程时游动阀打不开,甚至下冲程固定阀也有可能打不开,抽油泵出现“气锁”现象,影响泵的正常工作。

Research on Oil-Water Separation Efficiency and Pump Dynamometer Simulation Model for Injection-production System

Aiming at the exploiting problems caused by high water-bearing oil fields,based on the established mathematical model,the gas-liquid ratio of the injection pump and the production pump,the separation efficiency of oil and gas were calculated respectively and the relationship between gas-liquid ratio and separation efficiency was obtained.The movement law of the plunger and the compressibility of the fluid in the pump cylinder were comprehensively considered,the continuous flow equation of fluid in the pump cylinder was established.According to the continuous flow equation,the mathematical model of the relationship among the plunger movement law,the liquid pressure in the pump cylinder and the gas volume of the pump cylinder was established,the simulation model of the instantaneous liquid pressure and the pump dynamometers in the pump cylinder was established.The simulation results show that when the production gas-oil ratio GOR increases,the gas in the pump cylinder increases,which causes the open time of injection-production pump floating valve and the fixed valve to lag.When the production gas-oil ratio GOR increases to a certain extent,the volume occupied by the gas in the injection pump and the production pump chamber is large enough,not only does the upstroke floating valve not open,but also the downstroke fixed valve may not open.At this time,the oil well pump has an"air lock"phenomenon,which affects the normal operation of the pump.