Atomization of Liquids by means of a Rotating Nozzle : 2nd Report, Effects of Atomization Conditions on Droplet Sizes

Abstract

In this paper, the effects of such factors as the speed of rotation n (rpm), discharge velocity v₀ (m/s), diameter of the nozzle D_n (mm), and rotating diameter of the nozzle D_r (cm) on droplet sizes were examined with water giving consideration to the mechanisms of atomization described in the preveous report. The results may be summarized as : (1) As Figs. 7∼11 represent, the Sauter mean diameters d^^- do not decrease smoothly as the value of v is increased, but form five distinct stages, where v is a resultant velocity of v₀ and a peripheral velocity of the nozzle. The first stage marked by 1 in these Figs. corresponds to the mode of dripping, the second stage marked by 2 corresponds to the smooth jet, the third stage marked by 3 to the wavy jet, the forth marked by 4 to the partially strayed jet and the fifth marked by 5 to the spray. (2) Mean diameter d^^- (μ) is expressed by the formulae [numerical formula] for the region of wavy jet (stage 3), [numerical formula] for the region of spray (stage 5). (3) The maximum diameter d_max shows nearly the same tendency as d^^- (Fig. 15) and has the following relation : [numerical formula]