石油工程中环空流道液流失速水击特性的实验研究

发布时间：2018-01-09 00:08

本文关键词：石油工程中环空流道液流失速水击特性的实验研究　出处：《东北石油大学》2015年博士论文　论文类型：学位论文

【摘要】：石油工程中为了提高采收率的注水、洗井工艺中,液流常通过油套环空流动,此过程中由于机械故障或电机突然停止工作,使得环空液流的动力瞬间丧失,加上采油管道较长,会导致环空流道中的液流失速,产生水击现象。这种环空液流失速水击现象给采油工程安全及周边环境会带来严重影响,因此有必要对此现象进行研究。目前环空流道的液流运动研究中,主要是在同心环空(偏心环空)的定常流(非定常流)的控制方程、解析方法、以及边界形式对液流运动影响等系列问题上,研究的流体包括牛顿流体和幂律流体等,而对环空流道液流失速水击特性的研究未见报道。论文结合环空流道结构特点,推导了环空流道液流失速水击的波速计算公式,分析了公式中的摩阻项。然后通过粒子图像测速技术和智能数字动态压力采集系统,对竖直井模拟实验装置注水过程中正注、合注、反注以及水平井模拟装置中合注环空液流失速水击的压力场和流场特性进行了分析,并结合油套环空中流速分布变化及其衰减过程和涡量场等特性分析了其成因,同时结合实测的环空流道液流失速水击波速对其公式进行了分析。另通过模拟实验装置测试分析了油套环空和油管同时失速和各自失速液流产生水击时,偏心环空中液流流场和压力场的特性,总结了不同偏心度对各环空液流失速水击特性的影响。还通过模拟实验装置及PIV和瞬变压力采集系统对环空中螺旋流失速水击的压力场和流场参数进行了采集,利用参照美国类似标准设计的旋度涡角测量仪(申报了国家专利),测定了环空流道中螺旋流的不同旋度,进而对不同旋度环空中螺旋流的失速水击特性进行了分析研究。最后通过模拟实验装置对往复式抽油泵失速产生的阀门速关速开水击和阀门速关水击的特性进行了研究,为了对其特性进行剖析,引进了水击锤击数的概念,通过锤击数分析了往复式抽油泵失速水击阀门不同工作方式下水击的特点,以及对抽油泵环空流道液流运动的影响。研究结果表明：正注和合注时液流失速产生水击,会使油管内、外壁压力瞬时严重失衡,压力差最高可达数百倍,反注时油套环空内、外壁和油管内壁水击压力变化较平衡。正注油套环空内液流速度衰减快于油管,压力衰减慢于油管：油管内液流失速对油套环空液流有牵动作用。合注时,油套环空内速度衰减快,水击压力衰减也快;如失速时间不同步,油管和油套环空交合部可能产生二次水击。水平井等速合注时,环空流道中液流水击压力大；水击压力及流速衰减快,环空外壁水击压力大于内壁水击压力,内壁水击压力衰减快于外壁。偏心油套环空和油管内同时产生水击,随着偏心距的加大,油套环空内、外壁压力增加,油管内、外壁以及两侧水击压力双重失衡;偏心距越大,小流道内流速越小,油套环空流道内速度衰减越快；仅油套环空内液流失速产生水击,偏心距小,内、外壁压力差大,环空小流道侧速度衰减随偏心距的增加而加快；仅油管内液流失速产生水击,油管内、外壁压力差大。环空流道螺旋流失速水击发生后,流速在油套环空两侧流道内衰减是非同步对称的；断面流速波动和衰减震荡随旋度涡角变化：断面涡量不完全具有贴壁性,其随旋度涡角的增加而减小；油管内、外壁压力差,随涡角的增大而减小。往复式抽油泵失速后,阀门速开速关产生的水击,水击锤击数较高,高水击锤击数比率较大,水击压力小,水击锤击数衰减缓慢,水击衰减历时短；阀门速关产生的水击,水击压力大,水击锤击数沿程衰减快,水击衰减历时较长,水击锤击数少。
[Abstract]:Petroleum Engineering in order to improve the water injection recovery, washing process, fluid flow through the annulus flow often, this process due to mechanical failure or the motor suddenly stops working, the annular liquid flow dynamic moment lost, plus oil pipeline is longer, will lead to the annular flow channel of fluid flow in the stall, produce the water hammer phenomenon. The annular liquid flow stall phenomenon of water hammer has serious impact on the environment surrounding the safety and production engineering, so it is necessary to research this phenomenon. The annulus flow of fluid motion research, mainly empty ring in concentric (Pian Xinhuan space) the steady flow (unsteady flow) the analytic method of control equation, and the boundary of a series of problems such as the effect of fluid motion, the fluid including Newton fluid and power-law fluid, and the fluid flow of the annular channel stall water hammer characteristics has not been reported. The annular flow channel with the node The characteristics of the structure, calculation formula of velocity of the annular flow channel flow stall of water hammer, analyzes the friction formula. Then the particle image velocimetry technique and intelligent digital dynamic pressure acquisition system of vertical well simulation experiment device is in the process of water injection, water injection, anti injection and horizontal well simulation device co injection annulus flow stall water hammer pressure and flow field characteristics are analyzed, and combined with the oil ring air velocity distribution changes and its attenuation and vorticity field characteristics analysis of its causes, and combining with the actual annulus flow of liquid flow on the stall surge wave speed formula is analyzed. Through the simulation of the other experimental apparatus for testing analysis of oil casing annulus and tubing and stall and their stall flow water hammer, characteristics of eccentric annulus fluid flow field and pressure field, summarizes the different eccentricity of the annulus fluid loss velocity of water hammer. The effect of pressure and flow field parameters through simulation experiment device and PIV and transient pressure acquisition system of annular helical flow stall water hammer were collected, based on the reference standards for the design of similar America vortex rotation angle measuring instrument (declared national patent), different rotation of the spiral flow in the annular flow channel. Determination of water hammer characteristics of different rotation stall annular helical flow was analyzed. Finally through the simulation experiment device of characteristics of reciprocating pump valve quick closing speed stall the boiling water hammer and valve quick closing water hammer were studied, in order to analyze its characteristics, introduced the concept of water hammer click the number by hammering number characteristics of reciprocating pump water hammer valve stall in different modes of water hammer, and the influence of pump flow channel in annulus fluid motion. The results show that: the positive note and The liquid flow stall to produce water hammer injection, the oil pipe, a serious imbalance in wall pressure transient, pressure difference of up to hundreds of times, anti injection annulus, and the outer wall of tubing wall water hammer pressure changes are balanced. The annular liquid flow velocity in the oil decay faster than the slow decay in pressure pipe, tubing a: stall role on annulus fluid flow in the tubing flow. Co injection, fast decay annulus velocity, water hammer pressure decay quickly; such as stall time synchronization, tubing and annulus overlap may have two times of water hammer. The horizontal well water injection velocity, ring air flow liquid water hammer pressure; water hammer pressure and velocity attenuation, annulus wall water hammer pressure is greater than the inner wall of the inner wall of the water hammer pressure, water hammer pressure decay faster than the outer wall. The eccentric annulus and tubing and produce water hammer, as the eccentricity increases, annulus, wall pressure Increase of pipe wall, on both sides of the water hammer pressure double imbalance; eccentricity is large, small flow velocity, annulus flow velocity decrease more rapidly; only annulus fluid flow inside the stall to produce water hammer, small eccentricity, within the outer wall of the pressure difference, with the increase of eccentricity annulus flow velocity attenuation and speed up the small side; only in the tubing flow stall produce water hammer, pipe, wall pressure difference. The annular flow channel spiral flow water hammer stall occurs, the flow velocity in the annulus on both sides of channel attenuation is non synchronous symmetrical; velocity fluctuation and damping swing with rotation vortex ring angle: section of vorticity is not completely attached to the wall, with the rotation angle of vortex decreases; the oil pipe wall pressure difference decreases with the increase of vortex angle. Reciprocating pump stall speed, valve open speed off the water hammer, water hammer blow count is high, high water hammer hammer The ratio is large, the water hammer pressure is small, the number of water hammer decays slowly, and the water hammer decays for a short time. The water hammer and water hammer pressure generated by valve closing are large, and the number of water hammer strikes is fast, and the attenuation of water hammer is longer.

【学位授予单位】：东北石油大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：TE93

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