The collision efficiency between the charging droplets and charging aerosol particles considering the image force

Abstract

The collision efficiency of droplets and aerosol particles in the cloud has been extensively studied. However, most studies underestimated the effect of short-range image force when considering the effect of charge on collision efficiency. It is worth noting that the short-range imaging force has a large effect on the collision efficiency when the droplet is close to the aerosol particle. In this paper, a new method for analyzing the collision efficiency of droplets and aerosol particles in the cloud is proposed after considering the effect of image force. The concrete expression of collision efficiency is deduced and further quantitative analysis of collision efficiency is carried out through the research of collision model and theory. In addition, the effects of droplet radius and charging state on the collision efficiency of droplets and aerosol particles are studied. The results show that the presence of electric charges will improve the collision efficiency when the droplets or aerosol particles are charged. Therefore, the growth of water droplets in the cloud can be promoted by applying an electric charge, thereby increasing the probability of rainfall. It provides an idea for the future research of artificial rainfall.