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Question 16.5: At the mean diameter, U = 200 m/s, V f = 180 m/s, β1 = 43.9°...

At the mean diameter, U=200 \mathrm{~m} / \mathrm{s}, V_{f}=180 \mathrm{~m} / \mathrm{s}, \beta_{1}=43.9^{\circ} and \beta_{2}=13.5^{\circ} . The factor \lambda=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{0.86 \times 200 \times 180}{1.005 \times 10^{3}}\left(\tan 43.9^{\circ}-\tan 13.5^{\circ}\right)

 

=22.24 \mathrm{~K}

 

And   R_{s}=\left[1+\frac{0.85 \times 22.24}{288}\right]^{3.5}=1.25 

 

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

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