Enhancement of evaporation of droplet using EHD effect (3rd report, onset of instability of gas-liquid interface under electric field imposed stepwise)

An experimental study was conducted to investigate the onset of instability of a liquid surface under an electric field imposed stepwise. The critical voltages and the response times above which the liquid surfaces became unstable were measured under electric fields applied in two different ways. Instability criteria were derived theoretically using a modified Rayleigh-Taylor instability equation for the cases of a perfect conducting liquid and a perfect insulating liquid. According to the results of the experiment and theoretical analysis, consideration was made of the mechanism of the onset of EHD (electro-hydrodynamic) instability of the surface of liquid having a long electrical relaxation time.