天然气开采阻水装置AICD的设计和数值模拟

Design and numerical simulation of water restriction device AICD for natural gas exploitation

设计了一种具有2层挡板的改进型自动流入控制装置(AICD),用于天然气开采过程中的井下控水。分析了AICD控水、通气的流动机理,数值计算了水、气在AICD装置内的流动,得到压力场。分别计算出水和气的入口-出口压差。采用曲线拟合的方法,得到了压差-流量的函数关系。计算结果表明,水的压差远远大于天然气的压差,说明本文设计的AICD具有显著的阻水效果。

The autonomous inflow control device(AICD)is a downhole flow control device for oil and gas exploitation.It can inhibit the water flow into wellbore,delay water coning and prolong the service life of oil and gas wells.In this paper,an improved AICD with two layer baffles is designed for downhole water flow restriction.The mechanism of AICD was analyzed for the water flow restriction and the gas flow preservation.The gas flow and water flow in AICD are simulated numerically.The pressure field is calculated,and the inlet-outlet pressure difference of water and gas are calculated respectively.A curve fitting method is adopted to obtain the relationship between the pressure difference and the flow rate.Numerical results show that the pressure difference of water flow is much greater than the pressure difference of natural gas,indicating that our AICD has a significant effect for blocking water.