Factors influencing liquid breakup in electrohydrodynamic atomization

A series of experiments were conducted to produce fine liquid droplets using electrohydrodynamic atomization. The mode of electrohydrodynamic atomization depends on the flow rate of the liquid, the inner diameter of the needle tip, the distance between the needle tip and the ground electrode, the shape of the ground electrode, and the applied ac power. This work was performed to explore the experimental analysis for the flow pattern visualization of droplets, and the relationship between the voltage application and the behavior of liquid atomization. Uniform droplets of different sizes can be obtained at the inception of the spindle mode by changing the flow rate and the electric field. The droplet size also decreased when the flow rate was raised for the spindle mode. The type of breakup mode, either varicose wave or sinuous wave, was observed using image processing system. For flow rates of 2.0 ml/min, 2.7 ml/min, and 3.5 ml/min, the varicose wave occurred from 4 kV, and the sinuous wave and twisting wave occurred over 6 kV. The dripping phenomena are investigated when the flow rate and the applied voltage are too low. (C) 2004 American Institute of Physics.