李鹏,尹晓云,杨思远,胡可,邓小娇,刘少钧,MASTOBAEV Boris N
LI Peng,YIN Xiaoyun,YANG Siyuan,HU Ke,DENG Xiaojiao,LIU Shaojun,Boris N MASTOBAEV

• 1:中国石化西北油田分公司石油工程技术研究院
• 2:西南石油大学石油与天然气工程学院
• 3:新疆油田分公司吉庆油田作业区
• 4:中国石油勘探开发研究院

摘要(Abstract)：

针对水环输送稠油过程中不能一直保持环状流动形态的问题，基于VOF两相流模型、标准k-ε湍流模型及CSF表面张力模型，对油水环状流在水平管中的流动情况进行了模拟分析。应用控制变量法分析管壁粗糙度与静态接触角对水环稳定性的影响，通过油水两相体积分数分布特征、轴向速度分布特点、管道沿线压力变化特性等指标综合评价水环稳定性的强弱。结果表明：随流动时间和运行距离的增长，油水环状流经历了同心环状流-偏心环状流-不完全环状流-分层流的演变过程。随管壁粗糙度的增大和静态接触角的减小，水环维持稳定流动的距离增长，管道沿线的总压降减小。管壁粗糙度对轴向速度分布和油核偏心率基本没有影响，不同管壁粗糙度下轴向速度均呈对称状分布，油核偏心率均约为0.73；而静态接触角对轴向速度分布和油核偏心率有较大影响，随静态接触角的增加，速度分布由对称状分布转变为舌头状分布，油核偏心率由0.73上升到1.0。截面持油率不随管壁粗糙度与静态接触角的变化而变化，不同模拟条件下均约为0.74。因此在实际输送过程中，可对现场使用的管材进行内表面改性处理，适当增大管壁粗糙度和减小静态接触角，以提高黏稠油水环输送的稳定性。
For the problem of inability to always keep the annular flow pattern in the transportation process of heavy oil by water annulus，numerical simulations for oil-water annular flow through a horizontal pipe were performed by FLUENT software based on VOF two-phase flow model，standard k-ε turbulence model and CSF surface tension model.The effects of pipe wall roughness and static contact angle on the stability of water annulus were analyzed by adopting control variable method.The stability of water annulus was comprehensively evaluated by the distribution characteristics of oil-water two-phase volume fraction，axial velocity distribution characteristics and variation characteristics of pressure along the pipeline.The simulation results indicate that with the increase of flow time and running distance，the oil-water annular flow experiences the evolution process of concentric annular flow，eccentric annular flow，incomplete annular flow，and stratified flow.With the increase of wall roughness and decrease of static contact angle，the stable flowing distance of water annulus increases，and the total pressure drop along the pipeline decreases.The pipe wall roughness almost has no effect on the axial velocity distribution and oil core eccentricity.Under different wall roughness，the axial velocity distributions are all symmetrical，and the oil core eccentricity is about 0.73.Whereas the static contact angle has great influence on the axial velocity distribution and oil core eccentricity.As the increase of static contact angle，the velocity distribution changes from symmetrical to tongue-like，and the oil core eccentricity increases from 0.73 to 1.0.The oil holdup does not change with the change of wall roughness and static contact angle，which is about 0.74 under different simulation conditions.Therefore，in order to improve the stability of water annulus transportation of heavy oil，the inner surface of pipe materials used on site can be modified to increase the wall roughness and decrease the static contact angle properly in the actual transportation process.

关键词(KeyWords)： 稠油;水环;稳定性;管壁粗糙度;管壁润湿性;静态接触角
heavy oil;water annulus;stability;wall roughness;wall wettability;static contact angle

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金项目(51779212,U19B2012)

作者(Author): 李鹏,尹晓云,杨思远,胡可,邓小娇,刘少钧,MASTOBAEV Boris N
LI Peng,YIN Xiaoyun,YANG Siyuan,HU Ke,DENG Xiaojiao,LIU Shaojun,Boris N MASTOBAEV

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