Nowadays, the droplet–particle collision characteristics in the gas‐phase ethylene polymerization process are still unclear. The high‐speed photography and a quasi‐circle imaging approach are employed to study the collision interaction characteristics between liquid droplets and polyethylene particles. The liquid film evolution is studied through variations of the film thickness on the particle north pole, the dynamic contact angle, center angle and film thickness at the maximum extension. Results have found that for n‐hexane the threshold temperature of the recoil happening increases with increasing initial Weber number, but for 1‐hexene it is stable. Over 70°C evaporation and splash occurs immediately. Under low Weber numbers, the water droplet stays for damping oscillations, the reference stable height of which is linearly related to temperatures. Moreover, three regimes of film thickness variation with time are identified and mathematically described, while Regime 3 characteristics are found strongly dependent on the liquid species, Weber number, and particle temperature.

中文翻译：

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液滴与聚乙烯颗粒碰撞过程中液膜行为的实验表征

如今，气相乙烯聚合过程中的液滴-颗粒碰撞特征仍然不清楚。高速摄影和准圆成像方法被用来研究液滴和聚乙烯颗粒之间的碰撞相互作用特性。通过改变颗粒北极上的膜厚，最大延伸处的动态接触角，中心角和膜厚来研究液膜的演变。结果发现，对于ñ己烷的反冲极限温度随初始韦伯数的增加而增加，但对于1-己烯则稳定。超过70°C，立即发生蒸发和飞溅。在较低的韦伯数下，水滴停留在阻尼振荡上，其参考稳定高度与温度成线性关系。此外，确定并数学描述了三种膜厚随时间变化的机制，而发现方案3的特性强烈依赖于液体种类，韦伯数和颗粒温度。