管道内液固浆液输送的数值模拟

Numerical simulation of liquid-solid two-phase flow in slurry pipeline transportation

为了对管道内液固浆液输送的流动形态进行研究,建立了以颗粒动力学为基础的Euler-Euler双流体模型.在浆液流速大于临界沉积速度的情况下,模拟了不同浆液入口速度时的管道压力降,同时对管道内浆液输送液固两相流进行了研究:当轴向位置与管径之比大于50时,管道内浆液流动处于充分发展状态.此外还分析了在不同浆液速度下管道内液固两相的空间分布和浆液流动形态:在水平方向液相速度分布和固体颗粒相速度分布呈对称状态;垂直方向液相速度分布和固体颗粒相速度分布由于重力影响,不再呈对称状态.固体颗粒相速度分布与液相速度基本相同,两者之间的滑移速度很小,可以忽略.计算结果与实验值的比较表明,所建模型能有效地描述管道压力降和管道内浆液流动形态.

An Euler-Euler two-fluid model based on the granular kinetics was built to study on the flow patterns of liquid-solid two-phase flow in pipeline. The mean pressure gradients were simulated at different slurry inlet velocity. The transition and development of liquid-solid flow with distance of flow were investigated with liquid-solid flow reaching the fully developed pattern when the ratio of the distance of flow to tubular diameter was higher than fifty. Slurry flow patterns and volume fraction distributions were presented at different slurry velocity. The slip velocity magnitude was usually small, with the effect of the slip velocity on the slurry flow being negligible in the heterogeneous and sliding bed flow. The comparison of simulated results with experimental results showed that the presented model describes well tubular pressure gradients and slurry flow patterns.