带电射流非稳态破碎的可视化试验

王贞涛1; 2; 陈永钟1; 孔茜1; 杨诗琪1; 岑旗刚1

doi:10.3969/j.issn.1671-7775.2024.02.013

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江苏大学学报（自然科学版） ›› 2024, Vol. 45 ›› Issue (2) : 213-219. DOI: 10.3969/j.issn.1671-7775.2024.02.013

能源与动力工程

带电射流非稳态破碎的可视化试验

作者信息 +

Visualization experiment of instability breakup for electrified jets in electrostatic atomization

Author information +

文章历史 +

摘要

采用高速数码相机对毛细管带电射流破碎形态的演化过程进行了可视化研究，探讨了大流量下带电射流破碎的基本形态及射流不稳定破碎模式的转变，分析了物性参数、电压及液体流量对带电射流破碎模式的影响.采用半球形毛细管喷嘴研究锥射流模式向简单射流模式演化的过程，采用普通毛细管喷嘴对比研究去离子水和乙醇的静电简单射流雾化模式.结果表明：在特定电压下，随着流量增加，锥射流模式可以逐渐过渡为简单射流模式；当初始状态为射流时，随着电压增加，大流量下的去离子水静电雾化射流破碎模式主要为曲张不稳定破碎和鞭动不稳定破碎；表面张力较小的无水乙醇更容易产生破碎，还出现了鞭动辅助分叉模式和枝状破碎模式.

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.

导出引用

王贞涛1, 2, 陈永钟1, 等. 带电射流非稳态破碎的可视化试验[J]. 江苏大学学报（自然科学版）, 2024, 45(2): 213-219 https://doi.org/10.3969/j.issn.1671-7775.2024.02.013

WANG Zhentao1, 2, CHEN Yongzhong1, et al. Visualization experiment of instability breakup for electrified jets in electrostatic atomization[J]. Journal of Jiangsu University(Natural Science Edition), 2024, 45(2): 213-219 https://doi.org/10.3969/j.issn.1671-7775.2024.02.013

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