苏里格气田集输管线清管过程瞬态模拟

对清管过程中的两相流流体特征的研究有助于管线及上下游设备的设计及操作。为此，采用稳态Barua模型与具有较好组分追踪功能的TACITE编码瞬态模型对苏里格气田集气管线清管操作中两相流瞬时流动规律进行了研究，重点分析了通球过程中流型、液体流量、压力、清管速率及天然气水合物堵塞等工况的变化规律。结果表明：由于清管过程中地形起伏较大，流体出现了多种流型，液体流量与压力沿程波动较大；清管器速度在上升管段和下降管段的凹凸结合处由于前后压差的明显变化会发生较大的改变。通过对管道总持液量变化的分析，获取了清管后各阀组管线恢复稳态的时间。采用瞬态分析方法对清管器运行中温度变化研究的结论表明：各阀组在清管过程中没有天然气水合物的形成。进一步验证了清管节流理论的正确性。

Transient simulation of the pigging process of gathering pipelines at the Sulige fas field

The researches into fluid characteristics of two-phase flow during the pigging operation are beneficial to the design and operation of pipelines and upstream and downstream facilities. The TACITE code transient model, which has favorable composition tracking function and can perform dynamic analysis, and the Barua stable-state model have been adopted to study the transient flow rules of the two-phase flow of the gathering pipelines during the pigging operation at the Sulige gas field. The study focuses on the changing rules of flow pattern, liquid flow rate, pressure, pigging velocity, and hydrate formation, etc. The resuhs show that the fluids have several types of flow patterns during pigging operation because of the terrain changes; the liquid flow rate and pressure also change greatly along the line. The pig velocity changes a lot at the concave-convex joint sec-tion of the upward and downward pipeline because of the great changes of pressure difference. Through analyzing the changes of total liquid inventory of the pipeline, we acquired the time which the pipelines of each valve block need to restore the stable state after pigging operation. The researches into the temperature changes by the transient-state analysis method show that no hydrate has been formed during the pigging operation. This further demonstrates the validity of the pigging and throttling theory.