环形电极结构对喷雾形态与荷电效果的影响

为研究环形电极结构对静电雾化的影响,对不同环形电极结构下的静电场进行实验研究,得到其锥-射流模式下的喷雾锥角及液滴荷质比。根据实验工况对不同环形电极结构下静电雾化装置产生的空间电场进行数值模拟,得到其对空间电场分布的影响。结果表明,随着环形电极内径减小或厚度增大,环形电极周围的径向电场强度增大,而轴向场强并未有明显变化;喷雾锥角和荷质比随环形电极内径的减小或厚度的增大而增大。环形电极厚度及内径的改变使空间电场分布发生变化,从而影响喷雾形态及液滴荷电效果。本研究可为提高液滴荷电效果、合理设计静电喷雾装置提供技术参考。

Effect of Ring Electrode Structure on Spray Morphology and Droplet Charging

Electrode structure is an important factor affecting the charging effect of droplets. To study the effect of structure of ring electrode on the performance of electrospray, totally 12 kinds of ring electrodes based on the combination of different inner diameters (12mm,14mm, 16mm and 18mm) and thicknesses (1mm, 2mm and 3mm) were selected for experiments. In the experiment, the digital SLR camera was used for image acquisition, and the image was processed by software to obtain the spray cone angle. In the experiments, the voltage across the resistor was directly measured, and the droplet charge-mass-ratio was obtained by calculation. The effects of electrode structure on droplet charge performance and spray morphology were analyzed by comparing the spray cone angle and the droplet charge-mass-ratio. Based on the experimental condition, electric field of different ring electrode structures was calculated by numerically simulation, and its influence on the electric field distribution was obtained. The results showed that as the inner diameter of the ring electrode decreased or the thickness increased, the radial electric field strength around the ring electrode was increased, and the axial electric field strength did not change significantly. The spray cone angle and the specific ratio were increased as the inner diameter of the ring electrode decreased or the thickness increased. The variation of the thickness and inner diameter of the ring electrode changed the spatial electric field distribution, which affected the spray structure and droplet charging. The research results can supply some guideline for improving the charging performance of the droplets and rationally designing the electrostatic spray device.