Experimental Study Based On Micro-nano Electrostatic Spraying

Electrospraying technology is an important technology in nanofabrication.Understanding of electrospraying in nanoscale is important in flowmechanism of fluids,preparation of nanoparticles,metal corrosion.However,whether the theories in largescale are applied to that in nanoscale,which requires detailed experiments.In this paper,the electrospraying setup is used to study ejection voltage and different ejection modes in the electrospraying.The theories of traditional electrospraying are analyzed.The ejection voltage and the Rayleigh limit are calculated.The ejection voltages under different nozzles are measured in the electropraying setup.The experimental results show that the ejection voltages become smaller when the nozzles become smaller.The influences of the power’s polarity,surface tension and the pressure on ejection voltage are investigated.The interaction mechanism between various factors and ejection voltage is investigated.The influence of different solution concentration on electrospaying is analyzed.It has been found that the solution concentration has no effect on ejection voltage.However,there are different ion curves in diffferent concentration.The solution concentration affects ejection modes.It is proposed that the liquid charge is the main reason for different ejection modes.The Rayleigh limit theory is used for analysis.Besides,the solution concentration has effects on atomization in electrospraying.The electric field distribution in electrospraying is analyzed by Comsol.The relationship between electric field and position is studied.The electric field in simulation is compared with that in experiment.The consistency in electric field between simulation and experiment is verified.Besides,the velocity in electrospraying is compared with the velocity that is from N-S equation,which verifies the consistency between theoretical formulas and simulation results.