NUMERICAL ANALYSIS OF INTERNAL FLOW PHENOMENA IN A MULTI-BLADE CENTRIFUGAL FAN

Abstract

A three-dimensional, steady, incompressible, turbulent flow field inside a multi-blade centrifugal fan used in an air-conditioner has been analyzed numerically. Reynolds-averaged NavierStokes equations with the standard k-ε turbulence model have been discretized by the finite volume method. The calculation results have shown complex three-dimensional characteristics of the flow, especially in the blade passages near the shroud side. The results have revealed a boundary layer separation at the leading edge on the blade suction surface, the flow reversal from the high pressure region inside the volute to the low pressure region near the impeller inlet, the flow recirculation near the shroud side, a jet-wake pattern at the rotor exit, the pressure fluctuation on the blade surface, etc. Some of the numerical results agree well with previous experiment.