A new slip factor for centrifugal impellers

Abstract

A new simple but accurate correlation for the slip factor of centrifugal impellers is developed. The functional form of the correlation is obtained by investigating the radius of a relative eddy inscribed by two adjacent vanes and the exit circle of a flow channel in the impeller. Two functions are introduced to correct the slip factor obtained by the present relative eddy model with reference to previous analytical results of Visser, Brouwers and Badie and experiments. The proposed correlation is a function of the number of vanes (Z), vane exit angle (β'₂) and the inlet-exit radius ratio (r₁/r₂).