利用设计的实验装置研究了颗粒和颗粒微团受静电力牵引撞击荷电液滴过程。研究发现：部分颗粒到达荷电液滴表面后出现撞击反弹现象，当撞击角小于85°时，接近50% 的颗粒发生反弹；颗粒微团由于结构松散在撞击荷电液滴后发生解体，大部分子颗粒被排斥反弹。部分体积较大的颗粒微团由于吸收过量空间电荷导致极性与荷电液滴一致，受库仑斥力作用在接触液滴表面以前发生逃逸。细颗粒物出现反弹、解体以及逃逸等二次飞散现象明显降低荷电液滴对细颗粒物的捕集效率。
An in-house designed device is used to investigate the behavior of fine particles impacting the pendant charged droplet by electrostatic attraction. The results show that part of the particles bounce off the droplet surface after physical contact. Nearly half of the particles rebound when their impact angles are smaller than 85°. Due to the loose structures, particle clusters disintegrate when impacting the droplet surface, and most generated daughter particles rebound subsequently. The larger volume of particle cluster enables it to capture more free charge during its motion, which may even offset the initial polarity and result in repulsion by the charged droplet. The reentrainment caused by particle rebound and cluster disintegration or escape significantly reduces the capture efficiency of the charged droplet.
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