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Question 16.1: At the mean diameter, U = 200 m/s, Vf = 180 m/s, β1 = 43.9° ...

At the mean diameter, U = 200 m/s, V_{f}=180 m/s, \beta_{1}=43.9^{\circ} and \beta_{2}=13.5^{\circ}. The factor λ = 0.86 and \eta_{s}=0.85 and inlet temperature T_{1 t} is 288 K. Calculate the pressure ratio.

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\Delta T_{s t}=\frac{0 \cdot 86 \times 200 \times 180}{1.005 \times 10^{3}}\left(\tan 43.9^{\circ}-\tan 13.5^{\circ}\right)

= 22.24 K

and R_{s}=\left[1+\frac{0 \cdot 85 \times 22 \cdot 24}{288}\right]^{3.5}=1.25

[c_{p} of air has been taken as 1005 J/kg K]

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