Question: Air emerges from the axisymmetric nozzle shown in Fig. at a centerline velocity of 10tnl« at 1 atm pressure and 219C. Assuming an essentially constant-density and constant-temperature process (and this is ensured by the low velocity), calculate the displacement thickness of the boundary layer at the nozzle throat, assuming that the free-stream velocity along the inner surface of the nozzle varies linearly with distance; starting with u = 0 at the sharp corner. Calculate the air mass flow rate through the nozzle and the overall pressure drop through the nozzle. On the basis of these results, discuss the concept of a nozzle "discharge coefficient." What would be the discharge coefficient of this nozzle? If you were to define a Reynolds number based on throat diameter and mean velocity, how would the discharge coefficient vary with Reynolds number?
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