EHD喷印技术相关参数数值分析

目的对基于电-液耦合动力学原理(简称EHD)喷印技术的相关参数,进行锥射流和滴落模式下的数值分析研究。方法在锥射流模式中,对毛细凝结加热液体喷射的物理模型进行调整,以适用于EHD喷印;对滴落模式的液滴沉积过程,引入表面张力概念进行数值分析。运用数值法得到了锥射流的轮廓图,集中讨论了流量和净高度对射流直径的影响;重点研究了液滴直径与电压频率和液体表面张力之间的关系,并将理论结果与实验和经验数据进行了比较分析。结果锥射流模式在一定条件下,射流直径随着流量和净高度的增大而增加;在滴落模式中,得到的液滴直径随电压频率和流体表面张力的增大而减小,且数值分析得到的结果与实验结果相一致。结论对相关参数进行数值分析是对实验研究的补充,为EHD喷印技术研究提供了理论参考。

Numerical Analysis of the Relevant Parameters in EHD Micro-jet Printing

The aim of this work was to study the relevant parameters in electro-hydrodynamic (EHD) micro-jet printing technology for numerical analysis in cone-jet mode and dripping mode. In the cone-jet mode, the physical model of condensation-heating of capillary liquid jet was adjusted to be applicable for EHD printing; in the dripping mode, the concept of surface tension was introduced in the droplet formation process on the collector under pulse voltage for numerical analysis. The profile of Taylor cone in cone-jet mode was obtained using the numerical method, and the influence of the flow rate and net height on the jet diameter was focused; the correlations of droplet diameter and the pulse voltage frequency, the surface tension of the liquid in the dripping mode were emphasized, and the theoretic data were compared and analyzed with the experimental and experiential data. In the cone-jet mode, the jet diameter increased with the increase of the flow rate and the decrease of the net height under certain conditions; in the dripping mode, the droplet diameter decreased as the voltage frequency and the liquid surface tension increased respectively. The conclusions from numerical analysis showed good agreements with the experimental ones.