A numerical study of the effect of operating parameters on drop formation in a squeeze mode inkjet device

This study aims to investigate the ink droplet formation process of a squeeze mode piezoelectric printhead after an electrical pulse is applied by numerical analysis. The ink flow channel is modelled as a straight circular pipe ending in a convergent nozzle. The three-dimensional simulation system is based on the solution algorithm scheme for the solution of the governing equations of the flow field, and a volume-of-fluid method to predict the fluid interfaces is presented. The surface tension is modelled using a continuum surface force concept and thus computed as a function of the interfacial curvature. The pressure at the nozzle inlet, which is related to the applied voltage imposed on the simulation system, is determined by the propagation theory of acoustic waves. The effects of a pressure wave and cavity length on the droplet ejection process are presented.