超正压射孔井筒压力动态模拟分析

超正压射孔是1990年代发展起来的新技术,特别适用于碳酸盐岩裂缝性、非均质严重或污染严重的气层,由于良好的施工效果在国外得到很好应用.从超正压射孔的技术特点分析出发,阐述了超正压射孔的基本过程和增产原理;利用能量守恒方程和井筒液体运动方程,建立了超正压射孔井筒压力动态模拟数学模型;通过模型求解和结果分析,获得了井筒压力随时间的动态变化规律,它为超正压射孔裂缝扩展动态模拟和产能预测创造了条件.同时分析了不同液柱高度、气柱高度以及井口压力对施工压力曲线的影响,为超正压射孔工艺参数优化设计奠定了良好的理论基础.

The Modelling of Wellbore Pressure Performance During Extreme Overbalance Perforation

Exetreme overbalanced perforation developed in 1990's is very suitable for wells in carbonate or hihgly heterogeneous or heavy damaged gas formations and has been widly and well applicated because of its dramatic and cost-effective improvement in initial well productivity. In this paper, the principle and procedures of exetreme overbalanced perforation operations have been clearly addressed based on the analysis of technical characteristics. The wellbore performace equations have been derived according to energy conservation law and gas-liquid interface moving feature to model the wellbore pressure performance and the method of solving this problem has been carried out accordingly, it is shown that the wellbore pressure performance results are quite reasonable which provides basic information for modeling of fracture propagation and productivity prediction. The effect of wellhead pressure and gas/liquid column height on wellbore pressure performance have also been analysed, thus let the optimization of EOP job design be available.