摘要
在多簇密集切割压裂情况下,多缝间诱导应力干扰现象严重,使得优化射孔簇参数促进多簇均衡改造变得尤为重要。采用耦合岩石变形和流体流动的多簇限流射孔裂缝扩展模型,结合裂缝形态定量评价指标,展开限流射孔参数对裂缝扩展影响规律研究。结果表明:段内六簇射孔压裂时,密集切割使得多簇间诱导应力场影响区更为复杂,高孔密、均匀布孔时多裂缝非均匀扩展严重,应力阴影效应对段内中部裂缝延伸抑制明显。小孔径等孔径射孔及低孔密限流射孔策略可有效促进段内多簇裂缝均衡扩展;且非均匀限流布孔时,保持段内总孔数不变,增加段内中间两簇布孔数,同时降低段内两端孔数的限流射孔策略可有效优化裂缝形态,提高多簇射孔簇效率。
The induced stress interference is serious under the condition of dense cutting fracturing,which makes it more necessary to optimize perforation cluster parameters to promote balanced propagation from multi⁃ple perforation clusters.The fracture propagation model is proposed by coupling rock deformation and fluid flow,and fracture morphology quantitative evaluation index is established to study the fracture propagation law under limit entry perforating parameters.The results show that the influence area of induced stress field becomes more complex due to the dense cutting fracturing.For the case of high density and uniform distribution of perfo⁃ration holes,the heterogeneous propagation of multiple fractures is significant due to the induced shadow effect on the internal cracks.In the case of a fracturing interval with six perforating clusters,the strategy of small diam⁃eter and low perforating density can effectively promote the uniform propagation from multiple clusters.In the case of non-uniform limited perforating,keeping the total number of perforations unchanged,increasing the number of perforations in the middle two clusters,and reducing the perforation number at both ends of the same fracturing stage,the limited entry perforation strategy can effectively optimize the fracture morphology and im⁃prove the efficiency of multi cluster fracturing.
作者
卢宇
赵志恒
李海涛
刘畅
罗红文
肖晖
LU Yu;ZHAO Zhi-heng;LI Hai-tao;LIU Chang;LUO Hong-wen;XIAO Hui(School of Petroleum Engineering,Chongqing University of Science&Technology,Chongqing 431331,China;State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Southwest Petroleum University,Chengdu 610500,China;Shale Gas Research Institute of Southwest Oil&Gasfield Company,Chengdu 610051,China)
出处
《天然气地球科学》
EI
CAS
CSCD
北大核心
2021年第2期268-273,共6页
Natural Gas Geoscience
基金
重庆市教委科学技术研究项目(编号:KJQN202001514)
中国石油西南油气田公司“页岩气水平井段内多簇压裂优化设计研究”项目(编号:20190302-18)
重庆市自然科学基金项目(编号:cstc2019jcyj-msxmX0069)联合资助.
关键词
页岩储层
限流射孔
水力压裂
裂缝扩展
诱导应力
Shale gas reservoir
Limited entry perforating
Hydraulic fracturing
Fracture propagation
Induced stress
