螺旋射孔多孔眼起裂裂缝形态有限元模拟

发布时间：2018-04-07 16:42

本文选题：螺旋射孔完井　切入点：有限元模型　出处：《中国海上油气》2017年04期

【摘要】：采用螺旋射孔完井时,准确模拟不同孔眼周围裂缝的起裂形态能够有效指导射孔参数的优化。基于渗流-应力耦合方法建立螺旋射孔井有限元数值模型,引入损伤变量描述岩体破坏后的弹性参数、强度和渗透率随损伤的变化规律,进一步追踪模拟岩体损伤裂隙的演变过程,借此预测近井筒周围的水力裂缝起裂和扩展形态。模拟结果表明:采用耦合损伤变量的有限元模型能够模拟出沿井筒面和射孔方向扩展的两种水力裂缝的起裂及其随液压加载的扩展趋势;针对不同井筒方向条件可模拟出不同孔眼处水力裂缝的起裂差异,以此评估孔眼间水力连接性,并预测近井筒裂缝形态。室内物理模拟实验与数值模拟结果一致,表明建立的有限元数值模型可用于分析近井筒裂缝起裂的复杂性问题,对现场射孔压裂优化设计具有指导意义。
[Abstract]:When spiral perforation is used to complete wells, accurate simulation of fracture initiation patterns around different holes can effectively guide the optimization of perforation parameters.Based on the coupled seepage and stress method, the finite element numerical model of spiral perforating well is established. The damage variable is introduced to describe the elastic parameters, strength and permeability of the damaged rock mass.In order to predict the initiation and propagation of hydraulic fractures near the wellbore, the evolution process of the damage and fracture of rock mass is further tracked.The simulation results show that the finite element model with coupled damage variables can simulate the initiation of two hydraulic fractures along the wellbore surface and perforation direction and the trend of hydraulic loading.According to different wellbore direction conditions, the difference of hydraulic fracture initiation in different hole can be simulated, and the hydraulic connectivity between holes can be evaluated, and the fracture shape near wellbore can be predicted.The results of laboratory physical simulation and numerical simulation show that the finite element numerical model can be used to analyze the complexity of fracture initiation in near wellbore, and it is of guiding significance to the optimization design of field perforation fracturing.
【作者单位】：中国石油大学(北京)油气资源与工程国家重点实验室;中国石油长庆油田分公司;中国石油塔里木油田分公司;中国石油集团渤海钻探工程有限公司;
【基金】：国家杰出青年科学基金项目“石油工程岩石力学(编号:51325402)” 国家自然科学基金重大项目“页岩油气高效开发基础理论研究(编号:51490651)”;国家自然科学基金重点项目“页岩气开采岩石力学(编号:51234006)”部分研究成果
【分类号】：TE257.1

【参考文献】