水平管内黏稠油水环输送的稳定性

Stability of Water Annulus Transportation of Heavy Oil in Horizontal Pipeline

尹晓云 苏明 周鑫 张良 敬加强

YINXiaoyun SUMing ZHOUXin ZHANGLiang JINGJiaqiang

中国石油西南油气田分公司安全环保与技术监督研究院, 四川 成都 610041 页岩气评价与开采四川省重点实验室, 四川 成都 610041 国家管网集团西南管道有限责任公司建设项目管理中心, 四川 成都 610094 西南石油大学石油与天然气工程学院, 四川 成都 610500 油气消防四川省重点实验室, 四川 成都 611731

Safety, Environment and Technology Supervision Research Institute, Southwest Oil and Gas Field Company, PetroChina, Chengdu, Sichuan 610041, China Key Laboratory of Shale Gas Evaluation and Exploitation of Sichuan Province, Chengdu, Sichuan 610041, China Construction Project Management Center, PipeChina Southwest Pipeline Co. Ltd., Chengdu, Sichuan 610094, China Petroleum Engineering School, Southwest Petroleum University, Chengdu, Sichuan 610500, China Key Laboratory of Oil & Gas Fire Protection of Sichuan Province, Chengdu, Sichuan 611731, China

采用FLUENT软件，基于VOF两相流模型、标准$k$-$\varepsilon$湍流模型及CSF表面张力模型，模拟了油-水环状流在水平管中的流动情况，分析了流体性质(油-水密度差、油-水黏度比、油-水界面张力)对油水两相分布特征及水环结构稳定特性的影响。模拟结果表明，流体性质对截面平均含油率基本无影响，在不同模拟工况下均约为73%。但其对油水两相体积分数分布和水环稳定性评价指标(油芯偏心率、水环维稳长度比、管输压降)有显著影响，在模拟条件下，油-水环状流总体上呈上薄下厚的水层包裹位于管道上部的核心油流的偏心形态；当油相密度为996.4 kg/m$^3$，油相黏度为1 743.3 mPa·s，油-水界面张力为22.36 mN/m时，水环的稳定性最好。

In the present study, simulations for oil-water annular flow through a horizontal pipe were performed by FLUENT software based on VOF two-phase flow model, standard $k-\varepsilon$ turbulence model, and CSF surface tension model. The influences of fluid properties (oil-water density difference, oil-water viscosity ratio, and oil-water interfacial tension) on the distribution of oil-water two-phase and the stability performance of water annulus structure were analyzed. The simulation results indicate that the oil-water properties have no effect on the area-weighted average of the oil volume fraction, which is about 73% in various working conditions. However, they have a significant impact on the volume fraction distribution rules of oil-water two-phase and the stability evaluation indexes of water annulus structure (oil core eccentricity, stable length ratio of annular flow, and pipeline pressure drop). Under the simulated conditions, the oil-water annular flow in a typical eccentric form, where the oil-core located in the upper part of the pipe is wrapped by the upper thin and lower thick water layer. The stability of water annulus is at the best when the oil phase density is 996.4 kg/m$^3$, the oil phase viscosity is 1 743.3 mPa·s, and the oil-water interfacial tension is 22.36 mN/m.

10.11885/j.issn.1674-5086.2020.12.04.01