各向异性射孔水平井气井的产能评价

Deliverability Evaluation of Perforated Horizontal Gas Well in Anisotropic Formation

从气体的基本方程入手,采用气体标准压力概念得到气体的渗流方程,对渗流方程无量纲化。将射孔后的流动看成线源,根据Newman乘积原理,用Green函数的方法得到井底压力解析解。在此基础上,考虑井筒存储及压实和污染等产生的表皮,得到水平井气体标准压力与产量的关系。利用这一关系,可以预测水平井气井射孔后的产能。用实例对此进行了分析,得到了该气井的瞬时IPR曲线。

From the basic equation of gas and the concept of gas normalized pressure,the gas flow equation is derived,then make the equation dimensionless. Regard the gas flow after perforation line source,bases on Newman Multiplication Principle,a theoretical solution of the bottom hole pressure is obtained by Green Function method. Add the wellbore storage and skin effect caused by crushed-zoned and damage of formation,the function of the gas normalized pressure and production rate of horizontal well is derived. The deliverability of the gas well can be predicted. Example analysis of a perforated horizontal gas well is provided,and the transient IPR curve of the well is obtained.