应用Ω型管调整气液分层流动特性实验研究

摘要

To develop a passive approach for mitigating severe slugging in pipeline-riser systems,a new flow conditioner,Ω-shaped pipe,had been proposed.The Ω-shaped pipe was investigated experimentally under gas-liquid two-phase stratified flow conditions in a horizontal pipeline.The effects of the geometrical parameters of Ω-shaped pipe on its flow conditioning capacity and the flow conditioning mechanism were discussed based on the experimental data.It has been demonstrated that:after the gas-liquid flow passes through the Ω-shaped pipe,the fluctuation intensity and intermittency of liquid holdup time traces increased with increasing of standard deviation,maximum value,fluctuation range,cycle time and decreasing of minimum value.The gas-liquid stratified flow regime can be converted into an intermittent flow regime by Ω-shaped pipe,the flow conditioning capacity of which becomes stronger with the increase of the radius and count of the main bent and the effect of the distance between two adjacent bents is minor.The flow conditioning mechanism of the Ω-shaped pipe can be attributed to two physical processes:liquid blocking and gas carrying-over.The outcome of this study provides a foundation for optimizing the design of Ω-shaped pipes and applying Ω-shaped pipes to mitigating severe slugging in pipeline-riser systems.%为了开发抑制严重段塞流的被动式方法,利用所提出的新型流动调整装置—"Ω 型管"在水平管内气液分层流条件下开展了实验研究,讨论了 Ω 型管结构参数对其流动调整作用的影响规律,分析了 Ω 型管流动调整作用的机理.研究表明,气液分层流流过 Ω 型管后,液相截面含率的波动强度增加且间歇性增强,具体表现为波动曲线的标准差增加、最大值增加、最小值降低、波动范围增加和波动周期增加;Ω 型管能够将气液分层流调整为气液间歇流型,其流动调整能力随主弯管弯曲半径和基本单元个数的增加而增强,受基本单元之间距离的影响相对较小;Ω型管对气液分层流流动特性的调整作用机理可以归结为两个物理过程:液体阻塞和气体携带.研究结果为进一步优化设计 Ω 型管以及将其应用于立管系统以抑制严重段塞流奠定了基础.