An aeroplane is flying at 1000 km/h through still air having a pressure of 78.5 kN/m2 (abs.) and temperature – 8°C. Calculate on the stagnation point on the nose of the plane.

(i) Stagnation pressure,

(ii) Stagnation temperature, and

(iii) Stagnation density.

Solution:

Speed of aeroplane, $ V=1000 \mathrm{~km} / \mathrm{h}=\frac{1000 \times 1000}{60 \times 60}=277.77 \mathrm{~m} / \mathrm{s} \\ $

Pressure of air, $ \quad p_{0}=78.5 \mathrm{kN} / \mathrm{m}^{2} \\ $

Temperature of air, $ T_{0}=-8+273=265 \mathrm{~K} \\ $

For air : $ R=287 \mathrm{~J} / \mathrm{kg} \mathrm{K}, \gamma=1.4 \\ $

The …