Visualization experiment of instability breakup for electrified jets in electrostatic atomization
WANG Zhentao1,2, CHEN Yongzhong1, KONG Qian1, YANG Shiqi1, CEN Qigang1
（1. School of Energy and Power Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013, China; 2. Key Laboratory of Advanced Reactor Engineering and Safety, Ministry of Education, Tsinghua University, Beijing 100084, China)
Abstract：The high-speed digital camera was used to visualize the evolution of electrostatic atomization, where the capillary was considered as spraying nozzle. The morphology of electrostatic atomization pattern and the transformation of the instability breakup pattern at high flow rates were investigated, and the effects of physical parameters, applied voltage and liquid flow rate on the instability breakup of electrified jets in electrostatic atomization were explored. The evolution from cone-jet to simple-jet was studied using hemispherical capillary, and simple-jet atomization of deionized water and ethanol was conducted using common capillary. The results indicate that cone-jet mode can be gradually transfered into simple-jet mode with the increasing of flow rate at specific voltage. For the initial state of jetting, with the increasing of external potential, the instability breakup modes of simple-jet for deionized water at high flow rates are mainly varicose instability breakup and kink instability breakup. Anhydrous ethanol with low surface tension is easy to be overcome by electric force and easier to break, and the whipping assisted bifurcation and ramified modes also appear.
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