Abstract: Based on theoretical analysis,micro-experiment was carried out and the impact of high-voltage high-frequency pulsed electric field parameters on deformation of water droplet was investigated.The results showed that polarization relaxation time decreased with increasing electric field strength,while the deformation of droplet,migration velocity of polarization charge and electric field frequency corresponding to maximum degree of deformation of water droplet increased.The lower the electric field frequency,the larger the emulsion capacitance and the smaller the polarization voltage,the less the polarization deformation.With electric field frequency deviating from natural frequency of water droplet,resonance effect and drop deformation were suppressed.With increasing duty ratio,electric field acting on the droplet and deformation of water droplet increased.Part of the electric field energy leaked through the oil phase when duty ratio was large,which resulted in smaller deformation of water droplet.The interaction between parameters of high frequency pulse electric field acting on polarized deformation of the droplet cannot be ignored.The research results laid good foundation for further investigation of high-voltage high-frequency electrostatic emulsion-breaking mechanism.

Key words: high frequency impulse, electrocoalescence, polarization, deformation, demulsification

摘要： 在理论分析基础上进行显微实验,得到了高压高频脉冲电场参数对水滴极化变形的影响规律。结果表明,随电场强度的增加,水滴的变形度近似呈抛物线形增大,水滴的极化弛豫时间降低,极化电荷的迁移速度增加,水滴最大变形度所对应的电场频率增大。电场频率过低时,油水乳状液的电容较大,极化电压过小,极化程度较低;电场频率偏离水滴固有频率越多,水滴的振荡幅度及共振效应越差,水滴的变形受到抑制。随占空比的增加,作用于水滴的电场能随之增加,水滴变形度增加;占空比过大,部分电场能经油相发生泄漏,水滴变形度小幅降低。研究发现,高压高频脉冲电场作用下,各电场参数间的交互作用对水滴极化变形的影响不可忽略。上述研究成果为高压高频脉冲静电破乳机理的深入探讨奠定了基础。

关键词: 高频脉冲, 静电聚结, 极化, 变形, 破乳