Experimental Investigation on Transition Characteristics of Different Rotary Disk Configurations

An experimental study was performed to investigate the liquid granulation process on the rotary disks. Four groups of rotary disks were specially designed, and rosin/paraffin mixture was used as the working fluid. At first, the nondimensional transition equations between different breakup modes were obtained. Then, comparative analyses were performed to characterize the critical transition characteristics. Higher Q⁺ values for bulged-block disk from direct drop to ligament and ligament to fully ligament were observed, while the first appearance of the sheet mode nearly coincided for all types of disks. Finally the transition maps were proposed, and the effects of operational conditions and liquid properties on transition characteristics were analyzed. The transition maps showed that the broadest transition area from ligament to sheet mode was indentified in arc-edge disk, while the narrowest area appeared in bulged-block disk. Moreover, the transition between different modes was promoted by decreasing Q and ω or increasing μ.