通过流抑制和控制双极粉末充电
Simon Jantač1, Holger Grosshans1,2
1Physikalisch-Technische Bundesanstalt (PTB), Braunschweig, Germany.
Physical review letters
|February 16, 2024
概括
流通过改变粒子碰撞来抑制粉末的静电电荷. 这一发现对于提高工业粉末处理过程中的安全性至关重要.
科学领域:
- 粉末技术技术 粉末技术
- 流体动力学 流体动力学
- 静电学 静电学 静电学
背景情况:
- 工业粉末处理过程面临安全风险,原因是颗粒的双极电荷.
- 现有的模型预测不同大小的相同物质颗粒在接触时会收取相反的电荷.
- 不受控制的静电充电会导致危险的电荷积累.
研究的目的:
- 为了研究围墙流对粉末静电充电的影响.
- 了解空气动力学力如何影响粒子充电动力学.
- 为了确定缓解粉末流中危险电荷积累的机制.
主要方法:
- 模拟带有粒子载荷的流动,并结合流模型.
- 对粒子对粒子碰撞频率和结果的分析.
- 检查电荷分布和电位变化的情况.
主要成果:
- 围绕墙壁的流显著抑制了粉末中的双极充电.
- 空气动力学力量改变了碰撞动态,缩小了电荷分布.
- 中型粒子,而不是最小的粒子,表现出最负的电荷.
- 流会导致电荷分离,形成局部的高电位区域.
结论:
- 流提供了一种机制来控制和减少粉末中的静电电荷.
- 这些发现挑战了现有的模型,强调了流的抑制作用.
- 了解流引起的电荷分离是提高工艺安全的关键.
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