停输前后顺序输送混油特性的数值模拟

在地形复杂的地区,输送成品油时难免会经过高差、停输、下坡等不同工况的路径,而管道的倾角、停输的时间对下坡管道的混油特性有很大影响。借助于CFD的多相流模型,以三维倾斜管道为研究对象,分别就停输时间、倾角、输送顺序对混油特性的影响进行了数值模拟。研究结果表明:停输前,当前行汽油后行柴油时,管道的倾角越大,混油量越小,管道倾角越小,越易出现混油;当前行柴油后行汽油时,混油尾较长,倾角越大,混油量越大,管道倾角越小,混油量越小,但倾角对混油的影响较小;倾角对前行汽油后行柴油时混油量的影响大于前行柴油后行汽油时混油量的影响。停输后,在相同倾角下停输时间越长,混油量越大;在停输时间相同时倾角越大混油量越大。当前行柴油后行汽油时,随着停输时间的延长,混油越来越均匀,其倾角和管道的倾角一致,停输时间和倾角对前行汽油后行柴油时混油的影响较大。

Numerical Simulation of Mixed Oil Characteristics of Sequence Transportation before and after the Transportation Shutdown

In regions of complex terrain, refined oil will inevitably pass after elevation, shutdown, such as downhill different path. The pipe inclination angle and shutdown time of downhill pipeline blending have a great influence on mixed oil characteristics. Using CFD multiphase flow model and studying three--dimensional inclined pipe, on the shutdown time, angle and sequence transportation on mixed oil characteristics were numerically simulated respectively. The results of the study show that before shutdown while the forward gasoline and backward diesel, the dip angle is bigger, the mixed oil quantity is less~ the inclination angle is smaller, it is more prone to mixed oil. When the forward diesel and backward gas ,contaminated tail is longer and the inclination angle is bigger, the mixed oil quantity is bigger while the inclination angle is smaller, the mixed oil quantity is less but there is less effect on the mixed oil. The inclination angle has greater influence on the former than the latter. After shutdown, the longer the time of shutdown is, the more the mixed oil is with the equal angle. With the same time, the bigger the angle is, the greater the mixed oil. While the forward diesel and backward gasoline, with the shutdown time prolonging the mixed oil quantity is more and more uniform. When the inclination angle and the angle of pipeline is the same, shutdown time and angle has greater influence on the condition of the forward gasoline and the backward diesel.