Researches on the Observation on the Jetting of Liquid of High Viscosity and Droplet Control

Hong-wu Zhan*, Fang Xu, Ling-feng Lu
Zhejiang University of Technology, Hangzhou, China

© 2015 Zhan et al

open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: ( This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

* Address correspondence to this author at the Zhejiang University of Technology, Mechanical building B702, No.18, Chaowang Road, Hangzhou, P.R. China; Tel: +86-571-88320957; Fax: +86-571-88320957; E-mail:


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.

Keywords: 3D printing, droplet jetting, droplet observation, high viscosity.