In order to explore the dynamics of drop formation in the form of micro-dripping regime in electro-spraying

the micro-dripping of anhydrous ethanol was studied by a high-speed digital camera with a microscopic zoom lens

and the charge of microdroplet was studied by displacement. By recording the process of liquid accumulation

meniscus growth

elongation

deformation and separation of drops

the periodic characteristics of the drops release in micro-dripping regime were analyzed

and the dynamic process of droplets formation with the long/short axis and the equivalent diameter was discussed. The results show that the electro-spraying process in the micro-dripping mode presents periodicity

and the droplet release frequency increases with an increase in the electric Bond number. When the droplet release frequency ranges from 11.000 Hz to 65.360 Hz

the liquid flow rate hardly affects the drops release frequency. In the long/short axis characteristics of drops

the values of short axis/pipe diameter and long axis/pipe diameter increase as the dimensionless flow rate increases

whereas negligibly vary as the electric Bond number increases. The equivalent diameter presents a decreasing trend with an increase in the electric Bond number.