Theoretical And Experimental Study On Inductive Electrostatic Atomization

Electrostatic atomization is a kind of technology by which a liquid drop in a highvoltage electrical field can be divided into droplets whose diameters are in the micrometer grade. This paper is aimed at the preliminary research on the present situation of electrostatic atomization technology at home and abroad and in-depth studying about atomization mechanism of charged liquid combining theory with experiment. Through the means of the combination of theoretical analysis and experiment,we explore effect of the charged condition and material property parameters on the electrostatic atomization, especially the effect of voltage and electrical conductivity on the droplet size and distribution. For the part of theoretical analysis,we deepen to study the essence of atomization of the charged droplets, establish the mathematical model of high voltage electrostatic field and provides the theoretical basis for the follow-up experiments based on charged droplets characteristics and the study of charging methods and atomizing division.For the part of experimental study,we summarize the effect of voltage and electric conductivity on electrostatic atomization in the electrostatic atomization. By fitting the experimental data and the mathematical model of particle size distribution,we look for the law of the distribution of the droplets size,and strive to find a complete set of electrostatic atomization theory. The primary coverage of the research work is shown as follows:1.We give a detailed analysis of the droplet atomization process in high voltage electrostatic field in theory,fracture mechanism of the droplets in high voltage electrostatic field,and relationship between the droplet breakup and limitation of electric charged.2.We establish the mathematical model of charging electric field of the droplets,and the electric field were analyzed by Matlab.B Y a etailed analysis of the electric field intensity of the ring electrode axis and plane, we can provide a theoretical basis for experimental study.3.We analyse the droplets Conveying process in the high-voltage electrostatic field. According to the stress of droplets in the high voltage electrostatic field,we determin he equations of motion of charged droplet in the process of atomization and establish trajectory model of the charged droplets and provides the theory basis for the delivery and collection of the droplet.4.For the experiment, we study on modes of electrostatic atomization about charged droplets. By changing the electrode voltage,we observe different modes of electrostatic atomization, sum up the characteristics of each spray mode and summariz the law of the effect differ mode on the particle size.5.By changing the electrode voltage,we measure particle size corresponding to the different electrode voltage by Malvern Spraytec,and quantitativly analyse the relationship between particle size, distribution and the electrode voltage.6. On the basis of the first section of the experiment, we select solution of different electrical conductivity, measure particle size corresponding to the different electrode voltage and quantitativly analyse the relationship between particle size, distribution and the electrode voltage.7.By fitting the mathematical model of single peak of the droplet diameter-Rosin-Rammler distribution function with the experimental data, we find that the distribution function of linear regression linear regression is good and fitting to experimental data well.So the Rosin-Rammler distribution function can be used for prediction of single peak of unimodal distribution types of electrostatic spray droplet size and distribution. A probability density function with bimodal shape was introduced to establish the stati stics model to describe the droplets distribution characteristic at high voltage.We find that the mathematical model with bimodal shape can predict particle size distribution near the peak more accurately and has a big error to predict particle size distribution near peak edge.But, on the whole, the mathematical model with bimodal shape can fit to experimental data well.