INVESTIGATION OF SWIRLING FLOW IN DIFFUSERS INSTALLED AT THE EXIT OF AN AXIAL-FLOW PUMP

Abstract

The swirling flow in discharge diffusers with a converging rotating hub and diverging casing is modeled by reduced Reynolds equations, and a single-sweep method is used for their solution. The flow was probed at the inlet and outlet section of these diffusers under various pump capacities and, therefore, various swirl rates. The correspondence of results in the operating range of the pump was satisfactory concerning the velocity distributions in the outlet section as well as concerning the coefficient of energy losses. The characteristic curves of the pump with different internal angles of discharge diffusers are presented and the optimal internal angle is obtained.