高速非达西流动对产水气井产能的影响

Effect of high speed non-darcy flow on productivity for gas-well with producing water

在气藏开发过程中,井筒附近高速非达西流动是影响气井产能的重要因素。基于直井井筒周围平面径向渗流原理,考虑地层气水两相渗流以及井筒附近高速非达西流效应,定义气水两相拟压力,推导出了产水气井二项式产能公式。实例论证表明,产水使得气井产能大大降低,而高速非达西流动对气井产能影响较小,且产水后高速非达西效应将会减弱。本文研究可为产水气藏的开发提供理论基础。

During developing the gas reservoir, the high speed non-darcy flow near the wellbore in gas well will be an important factor which can lead to low productivity of gas well.Based on the theory of radial seepage near the vertical wellbore,the author considered the effect of high speed non-daryc flow and water production on gas well productivity, defined the pseudo-pressure of two phases,deduced the binomial productivity formula of gas-water well to calculate the productivity.Case study shows producing water will affect the productivity of gas well importantly,while the high speed non-darcy flow only affect the productivity a little,meanwhile after producing water,the effect of high speed non-darcy flow on productivity of gas well will become small.The study in this paper can lie the foundation for developing the water-bearing gas reservoir.