Design and Experimental Testing of an Electric Field-Driven Droplet Injection Device.

The properties of droplets produced by existing on-demand injection systems are typically determined by the nozzle diameter, i.e., only droplets with size larger than this diameter can be obtained. To solve this problem, a system for electric field-driven droplet injection and deposition was developed, and the related performances were compared with those of a standard pneumatic system. The results show that the diameter of droplets generated accordingly can be significantly smaller than the nozzle diameter. In particular, the effects of frequency and duty ratio on the number of droplets were studied by assuming microcrystalline wax as work material. A deposition matrix was obtained by using a nozzle with a diameter of 200 μm. The average diameter of the matrix was 80.17 μm with a standard deviation of 2.65 μm and the average spacing was 301.25 μm with a standard deviation of 6.80 μm. Four deposition states after droplet injection were considered and verified under different velocities of F60, F10, F3, and F0. We also provide an explanation for the existence of a series of inclined columns showing up during the deposition processs. [ABSTRACT FROM AUTHOR]