[论文解读] The effect of discontinuous injection on particle back-flow in pneumatic conveying systems

Otome Obukohwo, Andrew Sowinski+2 more|arXiv (Cornell University)|Jan 10, 2026

Granular flow and fluidized beds被引用 0

一句话总结

本文研究了在方管CFD-DEM仿真下，间歇性粒子注入频率如何影响上游粒子回流在气力输送中的作用。

ABSTRACT

Pneumatic conveying is used in many process industries to transport dry, granular, and powdered solids. The triboelectrification of particles during conveying causes particle agglomeration, spark discharges, and disruptions in particle flow, making particles move upstream against the fluid flow. The effect of frequency of particle injection on particle backflow is studied using CFD-DEM simulations. Conveying flow in a square-shaped duct with fluid frictional Reynold's number equal to 180, particle Stokes number equal to 8, and individual particle charge equal to 504 fC, is simulated with different particle injection frequencies. The proportion of particles moving upstream is found to increase as the delay period between injections increases, and the effect of the length of the injection period is minimal. Further, particles moving upstream are situated in low-drag zones at the corners of the duct where the electrostatic force dominates. In conclusion, the delay period between discontinuous injections plays a major role in particle backflow. The findings of the article are important for industrial processes with discontinuous injection of particles with a risk of particle accumulation within the conveying boundary.

研究动机与目标

• 激发对气力输送系统中摩擦电化与回流问题的理解。
• 量化注入频率与延迟如何影响向上游运动的粒子比例。
• 识别粒子向上游优先出现的空间区域。
• 评估间歇性粒子注入对工业过程的影响。

提出的方法

• 在方形导管中进行气力输送的CFD-DEM仿真。
• 设定流体摩擦雷诺数 Re = 180。
• 设定粒子Stokes数 St = 8 且粒子电荷 q = 504 fC。
• 改变粒子注入频率并测量上游粒子比例。
• 分析空间分布以识别低阻力区（角落）在电场力主导时的特征。

实验结果

研究问题

• RQ1 间歇性注入之间的延迟如何影响向上游移动粒子的分数？
• RQ2 注入周期的长度是否对回流有显著影响？
• RQ3 在导管的何处上游粒子更倾向居留，原因何在？
• RQ4 相对于流体阻力，静电力在造成回流中起到何种作用？

主要发现

• 注入之间的延迟越大，向上游移动粒子的比例越高。
• 注入周期的长度对回流影响很小。
• 向上游移动的粒子聚集在低阻力的角落区域，在那里电静力作用占主导。