弯管在输油管道中较为常见,多相流在突遇弯管时,易使流体的速度与压力发生突变,严重影响管道的安全输送.采用标准k-e模型,运用fluent软件进行仿真计算,模拟分析水平弯管内油水两相流动特性,研究不同油黏度、不同油水比例及不同流速度下的油水流动规律.结果表明:弯管内最大压力分布在外侧,最小压力分布在内侧;最大流速分布在弯管内侧以及弯管后直管段外侧.另外,弯管压降随原油黏度、原油含水率及流体入口速度的增大而增大,管内的最大流速与原油黏度以及流体入口速度成正相关,与原油含水率成负相关.
Bends are common in oil pipelines,while oil-water two-phase flow in the elbows is easy to cause velocity and pressure mutation,which seriously affects the safety of pipeline transportation.In this paper,the standard k-ε model and fluent software are used to simulate and analyze the characteristics of oil-water two-phase flow in a horizontal bend.,and the pressure and velocity distribution in the flow field in the elbow are obtained.Then,the flow laws under different crude oil viscosity,crude oil water content and fluid inlet velocity are studied.The results show that the maximum pressure is near the outer wall and the minimum pressure is near the inner wall in the elbow.The maximum flow velocity is distributed on the inner wall of the elbow and the outer side of the straight pipe behind the elbow.In addition,the pressure drop of the elbow increases with the increase of crude oil viscosity,crude oil water content and fluid inlet velocity.The maximum flow velocity in the pipe increases with the increase of crude oil viscosity and fluid inlet velocity,and decreases with the increase of crude oil water content.The results of analysis can provide reference for oil transportation and pipeline design.