Abstract
The characteristics of the swirl-type micro bubble generation device were investigated by changing the inflow diameter, the exit angle, and inner pressure. The performance of the micro bubble generation device was evaluated by the bubble diameter which was measured by the image measurement method. When the micro bubbles were generated, it was confirmed that there were two kinds of generation forms. In one form, the nozzle exit flow discharges in radial direction, and the other form, the flow discharges in axial direction. In radial flow out type, the axial flow velocity was widely distributed at the exit of nozzle, and causing strong recirculation zone in the central portion. And it was proved that the micro bubble became minuter in this discharge form, and the relation between the bubble diameter and pressure changed irregularly.