弯曲连续管内流体运动机理与摩阻研究  

Motion Mechanism and Friction Analysis of Fluid Flow in the Curved Coiled Tubing

作　　者：仝少凯 高德利[1,2] 岳艳芳 Tong Shaokai;Gao Deli;Yue Yanfang(MOE Key Laboratory for Petroleum Engineering,China University of Petroleum(Beijing);State Key Laboratory of Petroleum Resources and Engineering;PetroChina Huabei Oilfield Company)

机构地区：[1]中国石油大学(北京)石油工程教育部重点实验室 [2]油气资源与工程国家重点实验室 [3]中国石油华北油田公司

出　　处：《石油机械》2020年第3期134-139,共6页China Petroleum Machinery

基　　金：国家自然科学基金创新研究群体项目“复杂油气井钻井与完井基础研究”(51821092);国家自然科学基金重点项目“页岩和致密油气田高效开发建井基础研究”(U1762214);国家科技重大专项之子课题“高温高压钻完井管柱失效机理及安全控制技术”(2017ZX05005-005-007)。

摘　　要：井眼的弯曲直接影响连续管在井下的弯曲状态和连续管内流体的运动特性与摩阻。为此,分析了弯曲连续管内流体流动的运动机理,在此基础上根据流体力学原理建立了不同流体条件下弯曲连续管内流体摩阻计算模型。分析结果表明:弯曲连续管内流体的运动呈现断面环流和冲击波效应,这可能是引起弯曲连续管内流体复杂运动的力学机制;弯曲连续管内流体流动的断面环流和冲击波效应在一定程度上影响了连续管内流体的流态和摩阻;随着井眼曲率半径的减小和注入排量的增大,不同流体条件下弯曲连续管内流体的横向切力和摩阻随之增大;弯曲连续管内流体流动的横向切力和摩阻受弯曲段井眼曲率半径和注入排量的影响较大。研究结果可对弯曲井眼中连续管循环摩阻计算、受力分析和排量优选提供理论参考。The curveture of the wellbore directly affects the bending state of the coiled tubing in the well and the motion characteristics and friction of the fluid in the coiled tubing. To address the problem,the motion mechanism of fluid flow in curved coiled tubing is analyzed,and a calculation model of fluid friction in curved coiled tubing under different fluid conditions is established based on the principle of fluid mechanics. The analysis results show that the motion of the fluid in the curved coiled tubing presents circumfluence of section and effect of shock wave,which may be the mechanical mechanism that causes the complex movement of the fluid in the curved coiled tubing. The circumfluence of section and shock wave effect of the fluid flow in the curved coiled tubing affect the coiled tubing fluid flow regime and friction. With the decrease of the radius of wellbore curvature and the increase of injection displacement,the transverse shear force and friction of the fluid in the curved coiled tubing increase under different fluid conditions. The transverse shear force and friction of the fluid flows in the curved coiled tubing are greatly affected by the curvature radius of the borehole and injection displacement. The study results can provide a theoretical reference for the calculation of friction resistance,stress analysis and injection displacement optimization of coiled tubing in curved wellbore.

关 键 词：连续管 弯曲井眼 流体流动 运动特性 横向切力 摩阻 

分 类 号：TE934[石油与天然气工程—石油机械设备]