Abstract：The visual study of the electrostatic atomization modes of anhydrous ethanol and deionized water passing through metal single capillary was carried out by the highspeed camera with micro zoom lens. The typical electrostatic atomization modes of the single capillary and the law of droplet generation were explored. Changing the applied voltage and liquid flow rate, the release frequency characteristics of droplets under different atomization modes were discussed, and the variation law of droplet release frequency under different flow rates was investigated to obtain the relationship of release period characteristics with applied voltage and flow rates of droplets in discontinuous jet mode. The results indicate that the release frequency of droplets from the end of the capillary is increased with the increasing of applied voltage. There is a sudden increase in the droplet release frequency, and the induced voltage threshold values of anhydrous ethanol and deionized water are 3.0 kV and 5.0 kV, respectively. The sudden increase in release frequency varies from a few Hz to hundreds of Hz rapidly. By comparing the periodic characteristics of anhydrous ethanol and deionized water, it is found that the surface tension and conductivity of the liquids significantly affect the release frequency. The prediction formula for the maximum release frequency by theoretical analysis is proposed, and the prediction results are basically consistent with the experiment results.
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