On the Flow Structure Due to Corotating Disks With a Ventilated Hub

The effects of hub ventilation on the flow structure between corotating disks enclosed in a stationary cylindrical shroud have been studied using quantitative flow visualization. The ventilation flow resulted from the pumping of the rotating disks. The geometry of the ventilation holes and the total open area were varied and the flow structure was compared to the solid hub case. Many of the features present in the solid hub case remained in modified form. The radial extent of the region purged by the through-flow was independent of the hub open area, which ranged from 3.4 to 37.5 percent of the total hub area. Additionally, the radial extent of the purged region was found to be independent of the Reynolds number.