The axial velocity across an axial compressor blade is c z = 43.5 m/s, the average radius is r av = 0.2 m, and the stagnation temperature ahead of the rotor is T 0 = 300 K. The rotor blade is a...

The axial velocity across an axial compressor blade is c_z
= 43.5 m/s, the average radius is r_av
= 0.2 m, and the stagnation temperature ahead of the rotor is T₀
= 300 K. The rotor blade is a symmetric untwisted airfoil that rotates at 3600 RPM; the angle β₁–β₂
= 10◦. Calculate the following values:

(a) The angles β₁
and β₂.

(b) The change in the rotor tangential velocity,
c_θ
.

(c) The pressure coefficient of this rotor stage, C_p.

(d) The stagnation pressure rise p₀₃/p₀₁
across this stage (ηstage = 0.98, c_p
= 0.24, γ = 1.4).

(e) Degree of reaction R.

(f) During the starting process the axial velocity is reduced to c_z
= 20 m/s but the RPM stayed at 3600. How many degrees should the stator blade (ahead of this rotor) be rotated so that the rotor blade angle β₁
will not change?