An axial-flow compressor rotor at the pitchline has
a radius of rm = 0.5 m. The shaft rotational speed is ๐ = 6000
rpm. The inlet flow to the rotor has zero preswirl and the axial
velocity is constant, with Cz = 150 m/s. The stage has a 80%
degree-of-reaction at the pitchline where the solidity is ๐m =
1.2. The stage adiabatic efficiency is equal to the polytropic
efficiency, ec = 0.92.
Assuming that the inlet total temperature is Tt1 = 288 K,
๐พ = 1.4 and cp = 1.004 kJ/kg.K, calculate:
(a) rotor specific work at r = rm in kJ/kg
(b) stage loading, ๐, at r = rm
(c) flow coefficient, ๐, at r = rm
(d) rotor relative Mach number at the pitchline, M1r,m
(e) stage total pressure ratio at the pitchline
(f) rotor diffusion factor at the pitchline
(g) is the de Haller criterion satisfied?