径向孔眼辅助压裂裂缝形态  

FRACTURED MORPHOLOGY ASSISTED BY THE RADIAL BOREHOLE

作　　者：李小龙 肖雯 李建雄 刘耀华 张伟[1] 郭天魁 LI Xiaolong XIAO Wen LI Jianxlong LIU Yaohua ZHANG Wei GUO Tiankui(China University of Petroleum, School of Petroleum Engineering, Qingdao 266580, China Petroleum Engineering Technology Institute of Shengli Oilfield, Dongying 257000, China)

机构地区：[1]中国石油大学石油工程学院,山东青岛266580 [2]胜利油田分公司石油工程技术研究院,山东东营257000

出　　处：《大庆石油地质与开发》2017年第2期78-84,共7页Petroleum Geology & Oilfield Development in Daqing

基　　金：国家自然科学基金青年基金项目"径向钻孔引导水力压裂裂缝定向扩展机理研究"(51404288)

摘　　要：为研究不同径向孔眼参数对裂缝形态的影响规律,基于地层流-固耦合方程,应用ABAQUS有限元软件,利用最大拉应力准则判断裂缝起裂位置并预测裂缝扩展形态,最后通过大型真三维物模实验验证数模结果。结果表明:在径向孔眼内水力加压会改变原始地应力分布并形成干扰应力场;裂缝面由孔眼起裂并以缝高增长的方式扩展,当缝高增长超出干扰应力场后受水平地应力差影响转向;当同一水平面孔眼数量大于4时,干扰应力场即可互相连结成新的应力场;当以x、y轴均对称方式钻孔会形成形态复杂的多裂缝。径向孔眼对压裂裂缝具有引导能力,多径向孔眼具备构造复杂多裂缝的能力,利用径向孔眼对压裂裂缝的影响特性可有效提高传统压裂技术的改造效果,提高产能。In order to research the influence laws of different radial borehole parameters on the fracture morphology, based on the formation fluid-solid coupling equation, with the help of ABAQUS finite element software and maximum tension-stress criterion, the initial fractured position and propagation morphology were identified, and in the end, the numerical simulation results were verified by the large-scale true The conclusions show that the original terrestrial stress distribution is changed 3D physical simulation experiment. with the increase of the hydraulic pressure in the radial borehole; the fracture surfaces are cracked from the holes initially and propagated vertically, when the crack propagate beyond the interference field, due to the influence of the horizontal stress difference, the surfaces are forced to bend ; when the number of the borehole is over 4 in the same horizontal layer, the interference stress fields are formed a new conterminous stress field; when the radial wells perforated symmetrically to both X and Y axes, the multiple and complex fracture morphologies are generated. The guiding function of the radial bore- hole to the fractured cracks is presented, and moreover the capacity of the multi-radial borehole in the complex multi-fracture generation is confirmed, with the help of the influence characteristics of the radial borehole on the fractured cracks, the stimulated effects and productivity of the conventional fracturing technique can be effectively enhanced.

关 键 词：压裂 径向孔眼 裂缝形态 地应力 干扰应力场 

分 类 号：TE348[石油与天然气工程—油气田开发工程]