The production of droplets from liquid jets by capillary and electrohydrodynamic instabilities

2018-07-24T14:15:09Z (GMT) by Charles S. Parkin
The production of droplets from jets formed directly at nozzles was used in the lead shot production process where a nozzle was placed in the base of a tank of molten lead. A similar process is now used to obtain fertilizer prills where solid particles are produced from fertilizer melts by liquid jet break-up. This method could be extended to other materials such as metals and polymers where it is advantageous to obtain the material as solid spheres. The extension of this method to such materials requires a knowledge of the break-up behaviour of a wide range of liquids exhibiting both Newtonian and non-Newtonian behaviour. Since the more viscous liquids are difficult to break-up for the method to be successful in handling viscous liquids stronger forces than the naturally occurring capillary forces may be required. It is for this reason that the application of electrohydrodynamic forces to jets is considered in this thesis. It is of prime importance in most applications of jet break-up, after determining the conditions for instability, to determine the size of droplets formed. It is for this reason that this thesis is primarily concerned with the prediction of the size of droplets formed and also concerned with possible methods of monosize droplet production by liquid jet break-up.