Hydrodynamics of drop formation in liquid-liquid systems: investigation and interpretation of drop sizes in liquid-liquid systems as a function of nozzle diameter, nozzle velocity and physical properties of the systems

Drop formation processes from a nozzle of diameter 0.0602 cm in immiscible liquids were investigated experimentally and theoretically. Experimental data for drop sizes in prejetting and jetting regimes were obtained. In the prejetting conditions for water into decane system, data for drop formation time, drop diameter and drop velocities were obtained at three different Weber numbers using still photography and high speed cine film photographic techniques. A model has been developed to account for a two stage drop formation process in the prejetting regime. In the jetting regime three liquid pairs were employed with injection of dispersed phase from above and below the continuous phase to give a range of physical properties. Interfacial tension was varied from 3.1 to 27.5 mNm-1. The ratio of the continuous phase to the dispersed phase densities was varied from 0.73 to 1.36. The ratio of viscosities of the two phases was varied from 0.063 to 15.7. The experimental data for minimum drop size, mean drop size, jetlength and jet diameter were obtained from still photography. Experimental data for wave length, wave period, wave amplitude of the fastest growing disturbance on the jet were obtained by stroboscopic and high speed photographic techniques. A linear stability analysis for small scale hydrodynamics of the wave motion has been developed to predict the wave growth rate in the jetting regime. Patterns of drop formation and drop size variations in the intermediate regime were investigated and a semi-theoretical correlation was obtained to predict the drop size in the intermediate regime