2-MODE EHD STIMULATION OF A CONTINUOUS JET - GENERATION OF DROPS AND SATELLITES

This study reports the results of work carried out to investigate the high-frequency periodical break-up process of a liquid jet using an el ectrohydrodynamic (EHD) multimode jet stimulation device. The aims of this study were to optimize the different parameters and to generate d roplets of conducting fluid in a controlled fashion. In particular, th e experiments were performed for wavenumbers k less than or equal to 0 .5 with the second harmonic purposely introduced in the excitation sig nals. A dimensional analysis applied to the problem provided the main dimensionless parameters whose influence on jet break-up mechanisms we re examined. We found different regimes of break-up depending on both the electrostatic pressure ratio and the phase shift between the funda mental and the second harmonic. In addition, various patterns of drop production and boundaries between regions of parameter space with diff erent drop break-up behaviors were clearly identified using image proc essing techniques. Other features of jet break-up such as satellite dr oplet diameters and lifetimes were also considered in detail. Finally, our focus was to find the most suitable conditions for jet printer op eration.