缝面位移控制压裂裂缝同步扩展数值模拟  

Numerical Simulation of Fracture Synchronous Propagation Controlled by Plane Slit Displacement

作　　者：张鹏[1,2,3] 蒲春生[1,2] 胡淑颖 李南星[3] 宋运存 ZHANG Peng;PU Chun-sheng;HU Shu-ying;LI Nan-xing;SONG Yun-cun(School of Petroleum Engineering,China University of Petroleum(East China),Qingdao 266580,China;Key Laboratory of Unconventional Oil&Gas Development(China University of Petroleum(East China)),Ministry of Education,Qingdao 266580,China;TUHA Petroleum Research&Development Center,CNPC,Hami 839009,China;TUHA New Energy Center,Hami 839009,China;College of Mechanical and Electrical Engineering,China University of Petroleum(East China),Qingdao 266580,China)

机构地区：[1]中国石油大学(华东)石油工程学院,青岛266580 [2]中国石油大学(华东)非常规油气开发教育部重点实验室,青岛266580 [3]吐哈油田工程技术研究院,哈密839009 [4]吐哈油田新能源事业部,哈密839009 [5]中国石油大学(华东)机电工程学院,青岛266580

出　　处：《科学技术与工程》2023年第6期2381-2389,共9页Science Technology and Engineering

基　　金：中石油吐哈油田公司科技专项(2020)。

摘　　要：分段多簇压裂是非常规油气藏有效动用的重要工艺,压裂裂缝的复杂程度是提高单井产量和控制储量的基础,储层裂缝的扩展形态受地层物性,压裂工艺参数影响较为复杂。因此,为探索压裂裂缝同步扩展的形态特征及影响因素,建立了分段压裂缝面位移参数控制裂缝扩展数学模型,通过典型井取心岩心力学实验和数值模拟,结果表明:分段压裂簇裂缝的同步扩展形态与井斜角密切相关。井斜角在90°减小至0°时,裂缝扩展形态特征由双翼对称向双翼非对称转变,90°时簇裂缝向外侧发生偏转,且在裂缝尖端和应力阴影区,最大、最小主应力方向均发生转向,更利于复杂缝网的形成;小于90°时,裂缝向内侧发生偏转。分段压裂簇间的应力干扰作用强度与压裂排量值正相关、与簇间距离值负相关。压裂排量大小对提高裂缝的缝长和缝宽的扩展距离作用明显,能有效提高单井控制储量范围,但缝宽的扩展存在上限;簇间距10 m时,每孔排量不低于0.12 m^(3)/min才能有效形成簇间应力干扰;排量0.18 m^(3)/min,簇间距离小于20 m时,裂缝间的应力干扰显著,最大与最小主应力方向均发生转向,更好形成复杂缝网,簇间距离大于20 m时,不利于复杂缝网的形成。微地震裂缝检测证实,数值模拟结果与邻井微地震检测的裂缝扩展距离相符合,分段压裂在通过增大井斜角、提高压裂排量和缩小簇间距的方式,能有效提高非常规油气藏的缝网的复杂程度,进而提高非常规资源单井的产量和控制储量。Segmented multi cluster fracturing is an important process for effective production of unconventional oil and gas reservoirs.The complexity of fracturing fractures is the basis for improving single well production and controlling reserves.The expansion of reservoir fractures is more complex affected by formation physical properties and fracturing process parameters.In order to explore the morphological characteristics and influencing factors of synchronous propagation of fracturing cluster fractures,a mathematical model of segmented fracturing plane slit displacement parameters controlling double cluster fracture propagation was established.Through the core mechanical experiment and numerical simulation of typical wells,the results show as follows.The synchronous propagation of segmented fracturing cluster fractures is closely related to the well deviation angle.When the well deviation angle is reduced from 90°to 0°,the fracture propagation morphological characteristics change from symmetrical to asymmetric.At 90°,the cluster fractures deflect outward,and the directions of the maximum and minimum principal stresses turn at the fracture tip and stress shadow area,which is more conducive to the formation of complex fracture network.When it is less than 90°,the slit deflects to the inside.The intensity of stress interference between clusters of staged fracturing is positively correlated with the fracturing displacement and negatively correlated with the distance between clusters.Fracturing displacement has an obvious effect on increasing the expansion distance of fracture length and width,which can effectively improve the controlled reserves range of a single well,but there is an upper limit on the expansion of fracture width.When the cluster spacing is 10 m,the displacement of each hole is not less than 0.12 m^(3)/min to effectively form the stress interference between clusters.When the displacement is 0.18 m^(3)/min and the distance between clusters is less than 20 m,the stress interference between slit is sig

关 键 词：分段压裂 缝面位移控制 裂缝形态 应力干扰 

分 类 号：TE331[石油与天然气工程—油气田开发工程]