Investigation on the onset voltage and stability island of electrospray in the cone-jet mode using curved counter electrode

The objective of this study was to examine the effect of curved counter electrodes on the onset voltage and the stability island of the electrohydrodynamic atomization (EHDA) in the cone-jet mode. Five types of counter electrodes, regarding their curvature, and seven capillary nozzles with different diameters were used. Therefore, the effect of geometrical parameters on the onset voltage is investigated. Dimensionless numbers are used to help to generalize the results. These results are compared to the theoretical equation for the onset voltage. The results show the dependency of the onset coefficient on various parameters, specifically the counter electrode curvature. In addition, for a given configuration, the use of curved counter electrode led to about a 50% increase in the stability island area.