Change of atomization performance with selection of nozzle materials in electrohydrodynamic spraying

Abstract

In the present study, a series of experiments has been conducted for proper selection of nozzle materials to generate fine liquid (water) drops ranging between 30 and 450 mum through the electroydroynamic atomization process. The spindle mode was the primary drop-generation mode considered in this experimental work. Three nozzles made of different materials were prepared and tested: a stainless steel tube, and plain and metal (gold)-coated (except for the tip portion) silica tubes. The drop size distribution changed with the electrical conductivity and the surface wettability of the tubes, as well as with other parameters such as the liquid flow rate and the capillary tube voltage. Among these nozzles, the metal-coated silica tube showed the best performance in generating uniform, fine drops over a wide range of tube voltage because the pivoting motion and the sporadic corona could be suppressed.