Abstract：To realize the controllability of droplet size, velocity and spatial distribution characteristics generated by electrostatic atomization, the dynamic characteristics of electrostatic jet under different liquids, electric voltage and flow rate were experimentally investigated. The transient process of the electrostatic atomization was visualized, captured and analyzed through highspeed camera. By analyzing many highspeed images, the morphology difference of liquid filament between liquid drop and meniscus under various liquid properties, typical jet forms of pulsating and stable cone jets, and reference parameters range for propylene glycol and noctanol in different modes were obtained. The results indicate that in the conejet mode, the initial jet velocity from the meniscus is close to theoretical value. The varicose instability is found in the breakup of jet for propylene glycol and noctanol. The position of jet breaking point is changed with time and is mainly focused around twelve times dimensionless length ratio of jet breaking length to outside diameter of capillary nozzle. When the applied voltage or the liquid flowrate is too large, the stable cone jet mode is difficult to maintain and is gradually transformed into bifurcation, unstable multijet, oscillating jet and other unstable spraying modes.
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