Electrohydrodynamic atomization (EHDA) is a promising method for the fabrication of micro- and nanosized particles with narrow-size distribution and better morphologies in comparison to conventional methods of particle fabrication. A computational model was developed in this study to simulate the fluid and particle dynamics in an EHDA chamber, and thereby providing a means of predicting particle collection efficiencies at various operating conditions. Experiments were also conducted using a new design of the EHDA chamber. It was found that nitrogen flow rate, solution flow rate and voltage difference between the nozzle and ring can significantly affect the particle collection efficiency of the EHDA process. Electric field and electric potential profiles in the chamber were significantly affected by the combined voltages of the nozzle and ring. In general, a good qualitative agreement in particle collection efficiencies was obtained from experiments and simulations. The computational model developed in this study provided a means of understanding the various processes involved in micro- and nano-sized particle fabrication using the EHDA methodology. (c) 2012 American Institute of Chemical Engineers AIChE J, 2012