压裂气井产能预测新方法研究

New Methods of Productivity Prediction for Fractured Gas Wells

压裂气井产能预测是气井开发方案设计的重要基础,引入拟压力和拟时间函数建立封闭气藏点源渗流模型,采用源汇积分方法得到了无限导流垂直裂缝井井壁压力解析式,运用渐进分析及多元回归方法得到了拟稳态解析公式,同时利用Duhamel褶积通过数值反演得到了Fetkovich/Arps无限导流垂直裂缝井联合产量递减图版,并引入积分平均概念,进而得到了Fetkovich产量积分平均图版,最后对这种新的图版拟合方法的使用进行了实例说明,得到了产能预测参数,为压裂气井的产能预测提供了一种新方法。

The productivity prediction in the fractured gas well was an important basis of the development program design for gas wells.Therefore,a gas percolation model for enclosed reservoirs was established by introducing a pseudo-pressure function and a pseudo-time function,the analytical formula of a vertical fracture well was obtained by means of points source integral methods and a pseudo-steady-state formula was also obtained by using asymptotic analysis and multiple regression methods.Fetkovich/Arps productivity decline chart board and Fetkovich integral curves were obtained by Duhamel's principle and numerical conversion algorithm.An example of oilfield is explained by the new method,which provides a new method for predicting productivity of fractured gas wells.