The effect of electrical forces on the collection efficiency of millimeter-sized water drops collecting micron-sized aerosol particles has been investigated in a laboratory experiment. The observations show higher collection efficiencies for drops of 3.6- to 4.8-mm diameters than reported in some of the earlier studies for smaller drops. The limited and sparse data obtained in our experiments show that the collection efficiency of a drop is higher when it is charged or interacts with the aerosol in the presence of an electric field. The collection efficiency shows a maximum when the drop charge of either polarity is in the range of 10(-12) to 10(-11) C. The data show that the drop surface charge density required for this maximum decreases with the increase in drop size but is independent of the particle size. However, the peak value of collection efficiency is higher for larger particles. Moreover, the total charge on the drop required for this maximum remains almost constant at about 2-3 x 10(-12) C. The collection efficiency increases with the increase in the electric field, and the effect of the electric field is stronger for larger drops. In high fields, the drop collection efficiency shows a maximum for particles of diameter between 3.5 and 5 mu m. The change in collection efficiency for the same change in particle size is larger for higher electric fields. Distortion of large drops and the consequent charge accumulation on the rim of the drop has been proposed to explain the results. The decrease in collection efficiency for large values of drop charge and electric field support the drop-to-particle charge transfer during their interactions. [References: 14]
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机译：在实验室实验中已经研究了电力对收集微米级气溶胶颗粒的毫米级水滴的收集效率的影响。观察结果表明，直径为3.6至4.8毫米的液滴的收集效率要高于一些较早的研究中较小液滴的收集效率。在我们的实验中获得的有限而稀疏的数据表明，当液滴在电场存在下带电或与气溶胶相互作用时，液滴的收集效率会更高。当任一极性的液滴电荷在10（-12）到10（-11）C范围内时，收集效率都会显示出最大值。数据表明，此最大值所需的液滴表面电荷密度会随着液滴的增加而降低尺寸，但与粒径无关。但是，较大颗粒的收集效率的峰值较高。此外，该最大值所需的液滴上的总电荷几乎保持恒定，约为2-3 x 10（-12）C。收集效率随电场的增加而增加，并且电场的作用对于大滴。在高场中，对于直径在3.5到5微米之间的颗粒，液滴的收集效率最高。对于较高电场，相同粒径变化时收集效率的变化较大。已经提出了大液滴的变形以及随之而来的电荷在液滴边缘上的积累来解释结果。对于大的滴电荷和电场，收集效率的降低支持了滴与粒子之间的相互作用期间的电荷转移。 [参考：14]
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