水平气井不稳定产能分析  

Analysis on transient deliverability of horizontal gas wells

作　　者：蒋开[1] 何志雄[1] 李闽[1] 何家欢 刘忠群[3] 

机构地区：[1]西南石油大学油气藏地质及开发工程重点实验室,四川成都610500 [2]中国石油西南油气田公司勘探开发研究院,四川成都610500 [3]中国石化华北分公司勘探开发研究院,河南郑州450006

出　　处：《断块油气田》2010年第6期738-740,744,共4页Fault-Block Oil & Gas Field

基　　金：油气藏地质及开发工程国家重点实验室开放式基金项目"水平气井拟稳态渗流数学模型研究"(PLN1004);国家自然科学基金项目"异常高压气井(藏)开发动态模拟及最优控制研究"(50874094)

摘　　要：水平井能够数倍地增加储层泄气面积,有效提高气井产量,准确预测水平气井产能有助于合理开发产层,提高气藏采出程度。基于气体不稳定渗流理论,应用Newman乘积原理和Green函数得到了水平气井不稳定压降解析解。分别用半解析法和解析法对模型进行求解,对比讨论了如何取得合理的均流量点,并分析了水平气井产能随时间的变化规律。研究表明:沿水平井段单位长度井筒流量呈"U"型分布,随时间增加,"U"型面加深,均流量点从井筒两端向井筒中部移动,最后稳定在一点;根据半解析法得到的均流量点,用解析法对比误差不超过2%,产气量随时间的增加而不断减小,后趋于一定值,流动达到拟稳态。Horizontal well can greatly enlarge the drainage area and effectively raise the gas well production.Accurate prediction of horizontal gas well productivity can contribute to rationally exploit the gas pays,and enhance the degree of reserves recovery of gas reservoir.Based on the gas transient flow theory,the pressure drop analytical solution of horizontal gas well is concluded according to Newman′s product principle and Green function.Semi-analytic method and analytic method are respectively used for solving the model in order to discuss how to take the reasonable uniform flow point and to analyze the law of horizontal gas wells deliverability variation with time.The research shows that horizontal wellbore flow rate distributes in the form of U-type along the horizontal section,with the flow rate increasing with time and with the U-type surface deepening,and the uniform flow point moves from the ends to the mid-shaft,being steady at a point finally;that the error is less than 2% compared by the analytic method according to the uniform flow point obtained by semi-analytic method,and the gas productivity decreases as time increasing,tending to a certain value after a long time,and the flow reaches pseudo-steady state.

关 键 词：水平气井 不稳定产能 半解析法 解析法 均流量点 

分 类 号：TE312[石油与天然气工程—油气田开发工程]