Measurement of Relative Velocity Distribution in Centrifugal Blower Impeller

Abstract

The relative flow patterns of a centrifugal blower impeller were visualized on the hub, intermediate and shroud by the spark tracing method simultaneously visualizing stream lines, which indicate the flow direction. The stationary image of flow patterns in the impeller was observed using the rotating image stopping processor in which a traiangular prism rotated at half the angular velocity of impeller, and quasi three-dimensional relative flow velocity distributions were obtained. Experiments were carried out in the regions of small, design and large flow rates and the flow patterns of each region became clear. The surging phenomena were observed clearly at the small flow rate.