应力敏感影响下低渗透气藏水平井产能分析  

Productivity analysis of horizontal wells in low-permeability gas reservoirs considering stress sensitivity

作　　者：蒋艳芳[1] 张烈辉[1] 刘启国[1] 王心敏[2] 

机构地区：[1]"油气藏地质及开发工程"国家重点实验室.西南石油大学 [2]中国石油长庆油田公司第一采气厂

出　　处：《天然气工业》2011年第10期54-56,119,共3页Natural Gas Industry

基　　金：教育部博士点基金项目"三维大变化尺度缝洞型碳酸盐岩油藏复杂油水两相流动规律研究"(编号:20105121110006);国家重点基础研究发展计划(973计划)"碳酸盐岩缝洞型油藏注水开发研究"(编号:2011CB201005)

摘　　要：低渗透气藏不但存在启动压力梯度,而且还存在应力敏感。通过大量调研发现,在对低渗透气藏水平井产能研究中,更多的是考虑启动压力梯度的影响,而没有考虑应力敏感。为此,在前人研究的基础上,根据低渗透气藏水平井渗流特征,将其分为远井区和近井区,按照稳定渗流理论,推导出了同时考虑启动压力梯度和应力敏感影响的低渗透气藏水平井稳定渗流产能公式。在此基础上,进一步讨论了启动压力梯度和应力敏感对低渗透气藏水平井产能的影响。研究结果表明:启动压力梯度、应力敏感对低渗透气藏水平井产能的影响不可忽略;随着启动压力梯度和应力敏感系数的增大,低渗透气藏水平井产能降低,无阻流量减小。Besides the threshold pressure gradient(TPG),stress sensitivity should be considered in the development of low-permeability gas reservoirs.However,from a great number of related literatures,only the TPG is far more considered in the present studies of the horizontal well productivity in low-permeability gas reservoirs.In view of this,based on the previous research and according to the seepage flow characteristics,the low-permeability gas reservoirs are divided into far and close ones by the distance away from the wellbore.Then based on the theory of steady seepage flow,the equation of steady seepage flow deliverability for the low-permeability horizontal wells are deduced considering the influences of threshold pressure gradient and stress sensitivity.On this basis,their both influences on the horizontal well deliverability are further discussed respectively.The results show that their effects can never be ignored,and especially with the increase of the TPG and stress sensitivity coefficient,both the productivity of low-permeability gas reservoirs and the absolute open flow potential will decrease.

关 键 词：启动压力梯度 应力敏感 低渗透气藏 水平井 生产能力 线性流 平面径向流 球形径向流 

分 类 号：TE328[石油与天然气工程—油气田开发工程]