论文标题
关于气动输送过程中静电粉充电的CFD建模的审查
Review on CFD modeling of electrostatic powder charging during pneumatic conveying
论文作者
论文摘要
到目前为止，计算流体动力学（CFD）模拟无法可靠地预测气动输送过程中粉末的静电充电。缺乏预测工具是导致不必要的排放和增长的沉积物的原因之一，使植物成为爆炸的主要候选者。本文回顾了近年来数值模型的最新局限性和进步。特别是，讨论包括冷凝器模型，直到今天，该模型在粉末流动器的CFD模拟中最流行，但无法预测其大多数功能。新的实验导致了高级模型，例如不均匀的电荷模型，该模型可以解决非导电粒子表面上电荷的局部分布。此外，依靠表面状态理论的模型预测了由相同材料制成的多分散颗粒的双极充电。尽管这些模型通常是在CFD工具中使用Eulerian-Lagrangian策略实施的，但最近在Eulerian框架中成功描述了粉末充电。处理完整的粉末时，Eulerian框架在计算上是有效的。因此，这项研究可以铺平从学术研究到模拟粉末加工单元的道路。总体而言，即使用于粉末流量充电的CFD模型有所改善，但仍针对预测工具的重大障碍仍然存在。
Thus far, Computational Fluid Dynamics (CFD) simulations fail to reliably predict the electrostatic charging of powder during pneumatic conveying. The lack of a predictive tool is one reason for unwanted discharges and growing deposits that make a plant a prime candidate for an explosion. This paper reviews the numerical models' state-of-the-art, limitations, and progress in recent years. In particular, the discussion includes the condenser model, which is up to today most popular in CFD simulations of powder flow electrification but fails to predict most of its features. New experiments led to advanced models, such as the non-uniform charge model, which resolves the local distribution of charge on non-conductive particle surfaces. Further, models relying on the surface state theory predicted bipolar charging of polydisperse particles made of the same material. Whereas these models were usually implemented in CFD tools using an Eulerian-Lagrangian strategy, powder charging was recently successfully described in an Eulerian framework. The Eulerian framework is computationally efficient when handling complete powders; thus, this research can pave the way from academic studies to simulating powder processing units. Overall, even though CFD models for powder flow charging improved, major hurdles toward a predictive tool remain.
