基于FLUENT的90°弯管内水环流动特性研究

Study on Core-annular Flow Characteristics in a 90° Elbow Based on FLUENT Software

稠油由于其黏度过高,直接管输的难度较大,因此水环输送高黏原油作为一项高效节能的输油技术越来越受到关注.在高黏原油实际输送的过程中,水环会经过弯管部件,而在此过程中水环容易污染壁面,降低输送效率.运用CFD软件针对水环在90°弯管内的流动进行分析,通过不同流动参数的对比研究其维稳特性.结果表明:在模拟条件下,当流速增加至0.9 m/s时水环在离心力的作用下偏心严重;当油水密度比较小时,水环在浮力的作用下偏心严重,甚至可能污染壁面;在一定范围内改变黏度比对弯管中的环状流影响较小.该研究结果可为水环在90°弯管内流动参数优化提供理论参考.

Heavy oil is difficult to transport directly due to its high viscosity. Therefore,as an energy- efficient oil transportation technology,core-annular flow (CAF) has attracted more and more attention. In the actual transporting process,CAF will pass through the curved pipe parts,and CAF will easily pol- lute the wall and reduce the efficiency in this process. CFD software is used to study the flow of CAF in a 90° elbow,and its stable characteristics are studied by comparing different flow parameters. The results show that under the simulation conditions,when the velocity increases to 0.9 m/s,CAF is eccentric be- cause of the influence of centrifugal force. When the oil-water density is relatively small,CAF is eccen- tric because of the influence of buoyancy and it may even pollute the wall. However,changing the vis- cosity within a certain range has less influence on the annular flow in the elbow. The results could provide a theoretical reference for the optimization of flow parameters of CAF in a 90° elbow.