GENERATION, GROWTH AND COLLAPSE OF A BUBBLE IN CONDUCTIVE LIQUID HEATED DIRECTLY BY ELECTRIC-CURRENT

Bubbles generated in conductive ink heated directly by electric curren t pulses can be used in an ink-jet printer to eject ink-droplets. Such parameters as the time required for bubble nucleation, growth rate of the bubble, maximum radius of the bubble and electric power input req uired for bubble generation, which depend strongly on the shape and si ze of electrodes immersed in the ink, influence the performance of the printer. A method of numerical analysis was developed to investigate the temperature distribution of the ink and dynamics of the bubble, an d was confirmed to give values of the above parameters which were in g ood agreement with those of experiment. An optimum configuration of th e electrodes was suggested, based on the comparison of results calcula ted for different shapes and dimensions of the electrodes.