Acta Petrolei Sinica ›› 2019, Vol. 40 ›› Issue (1): 86-98.DOI: 10.7623/syxb201901007

• Petroleum Engineering • Previous Articles     Next Articles

Pressure loss experiment and numerical simulation of sand-carrying fracturing fluid in contraction-expansion pipe

Liu Jubao1, Yao Liming1, Li Xingyue1, Yue Qianbei1, Zhang Qiang1, Zhang Xiaochuan2, Zhang Hongyan2, Wang Haitao3   

  1. 1. Mechanical Science and Engineering College, Northeast Petroleum University, Heilongjiang Daqing 163318, China;
    2. Oil Production Engineering Rearch Institute, Daqing Oilfield Limited Company, Heilongjiang Daqing 163318, China;
    3. No.9 Oil Production Plant, Daqing Oilfield Limited Company, Heilongjiang Daqing 163318, China
  • Received:2018-07-17 Revised:2018-11-25 Online:2019-01-25 Published:2019-01-29

缩扩管内携砂压裂液的压力损失实验与数值模拟

刘巨保1, 姚利明1, 李星月1, 岳欠杯1, 张强1, 张晓川2, 张宏岩2, 王海涛3   

  1. 1. 东北石油大学机械科学与工程学院 黑龙江大庆 163318;
    2. 大庆油田有限责任公司采油工程研究院 黑龙江大庆 163318;
    3. 大庆油田有限责任公司第九采油厂 黑龙江大庆 163318
  • 通讯作者: 姚利明,男,1991年7月生,2014年获东北石油大学学士学位,现为东北石油大学机械科学与工程学院博士研究生,主要从事多相流及流固耦合振动研究。Email:327603785@qq.com
  • 作者简介:刘巨保,男,1963年12月生,1984年获大庆石油学院学士学位,2000年获浙江大学博士学位,现为东北石油大学机械科学与工程学院教授、博士生导师,主要从事杆管柱力学和固液两相流问题研究。Email:ljb@nepu.edu.cn
  • 基金资助:

    国家自然科学基金项目(No.11502051)、黑龙江省国家自然科学青年基金培育基金项目(2017PYQZL-09)、黑龙江省高校青年创新培养计划项目(UPYSCT-2018045)和东北石油大学研究生创新项目(YJSCX2015-023NEPU)资助。

Abstract:

The coupling between the turbulent flow formed by sand-carrying fracturing fluid and particle swarm dynamics is the source of pressure loss in contraction-expansion pipe. By building experiment system, this paper studies the pressure loss of the sand-carrying guar gum fracturing fluid in the contraction-expansion pipe, and the findings are shown as follows:the resistance-reducing ratio of contraction-expansion pipe presents an exponential decrease with the increase of flow rate and variable diameter ratio, while increases linearly with the increase of proppant mass concentration (sand ratio). Through fitting, an equation is obtained to calculate the resistance-reducing ratio of the sand-carrying guar gum fracturing fluid in the contraction-expansion pipe. Considering the dynamic coupling among turbulent flow, particle swarm collisions and accumulation of non-Newtonian fluids, a numerical analysis model and corresponding calculation method are established for solid-liquid two-phase coupling of sand-carrying fracturing fluid in the contraction-expansion pipe. The errors of numerical simulation results and the experimental pressure loss are not more than 10%, thus verifying the accuracy of the above numerical model and calculation method. The numerical simulation studies indicate that fluid velocity is larger than particle velocity on the contraction-expansion pipe end face, where the particle collision rate and stagnation rate are relatively high. There is a large vortex region on the contraction pipe end face, and the vortex flow rate increases with the increasing of proppant mass concentration. When the proppant mass concentration is increased from 0 (no particles)to 700 kg/m3 (sand ratio of 56%), the pressure loss of the contraction-expansion pipe is increased by 15%, which is basically consistent with the result obtained by experiment (16%). The increment in pressure loss of the sudden contraction pipe and the sudden expansion pipe is 22% and 12%, respectively.

Key words: fracturing fluid, contraction-expansion pipe, pressure loss, particle swarm, two-phase flow

摘要:

携砂压裂液在缩扩管内形成的湍流流动和颗粒群动力学耦合是产生压力损失的根源。通过建立实验系统,研究了携砂胍胶压裂液在缩扩管内的压力损失,得到了缩扩管降阻比随流量、变径比增加呈指数下降,并随支撑剂质量浓度(砂比)增大呈线性增加的变化规律,拟合出了携砂胍胶压裂液在缩扩管内的降阻比计算公式。考虑非牛顿流体的湍流流动和颗粒群碰撞、堆积的动力学耦合,建立了缩扩管内携砂压裂液固液两相耦合的数值分析模型和计算方法,其数值模拟结果与实验得到的压力损失误差均不大于10%,验证了数值模型和计算方法的准确性。经数值模拟研究表明:缩径和扩径端面区域存在流体速度大于颗粒速度以及高颗粒碰撞率和滞逸率现象,扩径端面存在较大旋涡区,且随支撑剂质量浓度增加旋涡流速增大;当支撑剂质量浓度从0增加到700 kg/m3(砂比56%)时,缩扩管压力损失的增加幅度达15%,与实验得到的16%基本一致,其中突缩管和突扩管压力损失的增加幅度分别为22%和12%。

关键词: 压裂液, 缩扩管, 压力损失, 颗粒群, 两相流

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