油品输送顺序对沿程混油量的影响

对顺序输送汽油前行柴油后行和柴油前行汽油后行的切换输送过程进行模拟分析,借助CFD仿真软件建立油品交替输送的三维流动传质耦合模型。模拟结果表明:2种输送工况的横向混油截面变化趋势均是以初期的弓形前锋曲面和随后逐渐变尖的锥形曲面向前行油品延伸;汽油前行的纵向混油截面变化,后行柴油是以逐渐变尖的楔形前锋曲面从管道底部嵌入汽油;柴油前行的纵向混油截面变化,后行汽油是以逐渐变尖的楔形前锋曲面从管道顶部嵌入柴油;黏度大的作为前行油品,边界层区域雷诺数小,管壁附近形成的混油层厚,侧面、顶面和底面边界层区域的混油量均是前行柴油后行汽油的输送方式混油量较大。

The Effect of Products Sequence on Contaminated Oil

Three-dimensional coupled flow and mass transfer model based on the analysis of the contrast of the different oil-delivered processes is built by CFD software. One process is delivering forward gasoline before down diesel and another is delivering forward diesel before down gasoline. The results show that these two processes have the same changing trends in the cross section of contaminated oil in the transverse direction. The down oil inserts into the forward oil by the arch form at the beginning. In addition, the taper conical surface is the final form of the down oil at the end of the process. In the longitudinal direction of the first oil-delivered process, the down diesel inserts into the forward gasoline by the dovetail form from the bottom of the tunnel. In the longitudinal direction of the second oil-delivered process, the down gasoline inserts into the forward diesel by the dovetail form from the top of the tunnel. The Reynolds number is small in the boundary layer region. The layer of contaminated oil is deep. They are based on the condition of the forward oil being replaced by the high viscosity oil. In all sections of the tunnel in delivering forward diesel before down gasoline, the quantity of the contaminated oil is large.