Abstract

Valve regulated droplet jetting is an important method for the generation of liquid droplet of high viscosity. Based on learning from piezoelectric micro-droplet jetting mechanism and researching methods, theoretical analysis and simulation were conducted on the factors affecting the micro-droplet jetting volume, and the qualitative relationship between the size of the jetted droplet and the feed pressure and striker stroke so as to guide the designing of the structure of the pneumatic valve control type nozzle and design the droplet jetting system and observation experiment platform based on stroboscopic techniques. Different jetting parameters was changed according to the results of the theoretical analysis for the conduction of jetting experiment, and several glycerin solutions at different solutions were taken as the working liquid for studying the effect of the several factors like feed pressure, pulse driving pressure, driving pulse width, and striker stroke. The striker would not be lifted to an ultimate position through controlling the pulse air pressure or driving pulse width so as to be able to jet extremely tiny droplet, but this is of rather bad stability. It is the most effective, stable and optimized method to control the striker stroke so as to change the diameter and shapes of the droplets.