A centrifugal compressor fitted with 21 radial vanes with an outside diameter of 40 cm is designed to operate at a rotational speed of 17,400 rpm. Assuming that the air admitted is at 101.3 kPa and a temperature of 15°C, determine
a. the absolute Mach number of the flow at the impeller tip given that the radial velocity at that location is 30 m/s;
b. the stagnation pressure of the air leaving the impeller if the total-to-total efficiency of the impeller is 92%;
c. the mass flow of air passing through the compressor if the axial width of the passage at impeller exit is 2.0 cm
Assume the Stanitz expression for the slip factor. Take Cp = 1005 J/(kg K) and γ= 1.4.