摘要
地形起伏地区的湿天然气集输过程中,湿天然气中的水分容易聚集在管道底部位置较低的区域,并形成积液,进而引发液塞的形成,使得管道内流量及压力发生剧烈波动。为准确获得气液两相液塞的起塞过程及特征参数,建立内径为150 mm、长16.5 m的起伏管线模型,利用VOF界面捕捉方法建立三维数值模型,对液塞起塞进行数值模拟研究,得到了液塞体的相分布,压力、速度分布,气液界面的起塞和演化过程,以及积液液面起塞的临界表观气速;分析了表观气速及积液量对液塞形成时管道压降的影响。模拟结果表明:积液液面由于KelvinHelmholtz不稳定效应形成液塞;液塞头部速度及上半部分液体速度对液塞的运动起决定作用;液位高度与管径之比小于0.6时,不形成液塞;液塞形成时的压降会随表观气速及积液量的增加而增大。
In the gathering and transportation process of the wet natural gas in rolling terrain,the water in the wet natural gas easily accumulates at the low point of the pipeline and becomes liquid loading,which causes the liquid slug and makes the flow rate and pressure in the pipeline sharply fluctuate.In order to accurately obtain the slug formation process,characteristics and parameters of the liquid slug of gas-liquid,the model of pipelines in rolling terrain with 150 mm of inner diameter and 16 m of length is established,and the three-dimensional model is established by VOF interface tracking method to do numerical simulation study of slugging and liquid slug.The phase distribution,pressure and velocity of the liquid slug,the process of slug formation and growth,and the critical superficial gas velocity of the slug formation of liquid loading are obtained; the effects of superficial gas velocity and liquid volume on the pressure drop during field slug formation process are analyzed.Simulation results indicate that the liquid slug formed due to Kelvin-Helmholtz instability effect; the velocity of the liquid slug head and the upper part of the liquid slug decide the movement of the liquid slug; the liquid slug cannot form when the ratio of liquid level to pipe diameter is less than 0.6; the pressure drop during the liquid slug formation will increase with the increase of superficial gas velocity and liquid volume.
出处
《油气田地面工程》
2017年第10期12-16,共5页
Oil-Gas Field Surface Engineering
基金
国家自然基金项目"多起伏湿气管线中积液/固体颗粒冲刷腐蚀机理研究"(51444005)
关键词
气液混输
起伏管道
积液
液塞
数值模拟
VOF模型
gas-liquid mixed transportation
pipeline in rolling terrdin
liquid loading
liquid slug
numerical simulation
VOF model
