浅层薄差油层水平缝多层同步压裂干扰数值模拟  

Numerical simulation of multi-layers horizontal simultaneous fracturing for the shallow,thin and poor reservoir

作　　者：潘林华 王海波 贺甲元 李凤霞 周彤 李小龙 PAN Linhua;WANG Haibo;HE Jiayuan;LI Fengxia;ZHOU Tong;LI Xiaolong(Research Institute of Petroleum Exploration and Production,SINOPEC,Beijing 100083,China)

机构地区：[1]中石化石油勘探开发研究院,北京100089

出　　处：《东北石油大学学报》2020年第6期114-124,I0008,共12页Journal of Northeast Petroleum University

基　　金：中国博士后科学基金项目(2019M660935);国家自然科学基金项目(51604050)。

摘　　要：浅层薄差油层水平缝多层同步压裂过程中,受裂缝干扰作用影响,不同储层的水平缝扩展程度存在差异。考虑套管、水泥环和多个储、隔层影响,采用流—固耦合的有限元数值模拟方法,建立三维浅层薄差油层水平缝多层同步压裂干扰数值模型,分析压裂层数、裂缝间距、储层特征和施工参数等对水平多裂缝干扰和裂缝扩展的影响。结果表明:数值模拟与裂缝扩展实验结果吻合较好。压裂裂缝位置对裂缝扩展具有重要影响,上、下端的压裂裂缝更易形成有效裂缝,中间压裂裂缝易受裂缝干扰影响而发生止裂;同步压裂层数越多,压裂裂缝间干扰作用越强;裂缝间距增大,压裂裂缝间的干扰作用降低;储层渗透率和孔隙压力增大,压裂裂缝间的干扰作用增强,中间射孔压裂的有效裂缝半径降低;中间射孔的压裂裂缝对施工排量的变化敏感,随施工排量增大,中间压裂裂缝的有效裂缝半径呈先增后减的趋势。对于不同储层的压裂施工设计,需要确定最佳施工排量及其他施工参数。该结果对多层水平缝压裂设计与施工具有指导作用。During multi-layers horizontal simultaneous fracturing of shallow,thin and poor reservoir,there are difference of horizontal fracture propagational degree at different reservoir,due to the influence of fracture interference.In order to study the fracture propagation and interference of multi-layers horizontal simultaneous fracturing,a three-dimensional multi-layers hydraulic fracturing fracture propagation model,accounting for casing,cement sheath,multiple layers and barrier interlayers,was built with finite element method combined with fluid-solid coupling.The numerical model was used to study the effects of the number of multi-layers,the interval between fractures,the characteristics of reservoirs,and fracturing parameters on horizontal multi-fracture interference and fracture propagation.The results show that the numerical simulation is in good agreement with the experimental results of fracture propagation.The location of fracturing fractures exert an important effect on fracture propagation.The hydraulic fractures at the upper and lower ends are more likely to generate effective fractures,and the middle fractures are easily affected by fracture interference to prevent fractures.The number of multi-layers horizontal simultaneous fracturing increase,the interference effects among hydraulic fractures become more strong.The interference effects among hydraulic fractures reduce with the fracture spacing distance increase.The permeability and pore pressure of reservoir increases,the interference effect among fracturing increase,the hydraulic fracture effect radius of middle perforation reduce accordingly.The hydraulic fracture of middle perforations is sensitive to pump rate.The pump rates increase,the effective fracture radius of middle perforations increase at first and then decrease.The numerical model and simulational results have guiding role for the fracturing design and treatment of multi-layers horizontal simultaneous fracturing.

关 键 词：薄差油层 水平缝 同步压裂 裂缝干扰 数值模拟 

分 类 号：TE357[石油与天然气工程—油气田开发工程]