Flow and Heat Transfer Characteristics on Circular Impinging Jet Added Annular Suction Flow

The Case Where Impinging Wall is Placed in Potential Core Region of Free Jet

Abstract

Cooling characteristics of the heating wall by the circular free jet added the annular suction flow, was examined. This experiment was carried out the case where the impinging wall is placed in the potential core region of the circular free jet. As a result, it was found that the higher Nusselt number is obtained in the case where the suction flow is added than in the case where the suction flow is not added independent of the distance between the exit of the pipe and the wall. Furthermore it was found that as the distance increases, the ratio of the suction velocity to the jet velocity showing the maximum Nusselt number becomes small. It was clarified by using PIV that these heat transfer characteristics are closely related with the fluctuating velocity and the time mean velocity.