A centrifugal pump delivers 50 dm3 /s of water at an impeller speed of 1450 rev/min. The impeller has eight vanes inclined backward to the direction of rotation with an angle at the tip of β'2 = 60° . The diameter of the impeller is twice the diameter of the shroud at inlet and the magnitude of the radial component of velocity at impeller exit is equal to that of the axial component of velocity at the inlet. The impeller entry is designed for the optimum flow condition to resist cavitation (see Eq. (7.20)) has a radius ratio of 0.35 and the blade shape corresponds to a well-tested design giving a cavitation coefficient σb = 5 0.3. Assuming that the hydraulic efficiency is 70% and the mechanical efficiency is 90%, determine
a. the diameter of the inlet;
b. the NPSH;
c. the impeller slip factor using Wiesner's formula;
d. the head developed by the pump;
e. the power input.
Also calculate values for slip factor using the equations of Stodola and Busemann, comparing the answers obtained with the result found from Wiesner's equation.