井下排水采气用雾化喷嘴的数值仿真研究

针对油气井、煤层气井排水采气工艺技术存在因积水影响正常采气的问题,提出利用井下雾化喷嘴技术方法,使井下气液两相流经过雾化喷嘴后形成液相粒径更小的雾状流,充分利用气相携带液相的能力将气液两相一起举升至地面井口,从而达到排水采气、提高气井产量和延长其生产寿命的目的。通过对喷嘴雾化理论的分析,并结合特定井下气液混合物的实际工况,应用流体仿真软件Fluent对雾化效果进行了仿真研究,并给出了仿真结果与理论结果的对比分析。分析表明,通过雾化喷嘴对井下液相的雾化作用,可以达到排水采气之目的。

Digital simulation research on the downhole atomized nozzle for dewatering gas recovery

Considering the problem that the hydrops existing in dewatering gas recovery for oil-gas wells and coal bed methane wells affect normal gas recovery,the technological method to utilize the downhole atomized nozzle is put forward,so as to make the borehole gas-liquid two-phase flow change into the mist flow with smaller liquid-phase particle diameter when it passes through the atomized nozzle. The capacity of the gaseous carrier fluid is fully utilized to lift both gas and liquid phases up to the ground wellhead,so as to achieve the purpose of drainage and gas recovery,increase of gas-well production and lengthening of the well's production life. Based on the theoretical analysis of nozzle atomization and the practical operating conditions of particular borehole liquid-gas mixtures,a simulation research on atomization effect has been performed by applying the fluid simulation software named Fluent. A comparative analysis of the simulation results and theoretical results has been made. The analysis shows that the purpose of dewatering gas recovery can be achieved by utilizing the nozzle to atomize the borehole liquid phase.