Experimental investigation on the air-liquid two-phase flow inside a grooved rotating-disk system: Flow pattern maps

An experimental system has been built up for the flow pattern analysis inside an open grooved rotating-disk system. The geometric construction and the governing parameters of the open grooved rotating-disk are presented. The measured results indicate that three different flow patterns appear in the flow field with the change of liquid flow rates and disk gaps. The flow patterns include the stratified flow, the full liquid flow, and the bubble flow. The transition of the air-liquid stratified flow to the full liquid flow is caused by an insufficient flow supply. The dimensionless liquid flow rate and the gap Reynolds number determine the transition boundary between the stratified flow and the full liquid flow. The shear force and the surface tension force of the liquid play a leading role when the full liquid flow transfers to the bubble flow. The Weber number and the gap Reynolds number can be applied in the boundary calculation for the full liquid to bubble flow transition. The two-phase flow pattern maps can be used for identifying the transition from one flow pattern to another inside the grooved rotating-disk system.