Air at 300 kPa, 63oC, and a velocity of 423 m/s enters an insulated duct of varying cross-sectional area. The air exits at 150 kPa, 88oC. At the inlet, the cross-sectional area is 6.57 cm2.
Assuming the ideal gas model for the air and variable specific heats, determine:
a) the exit velocity, in m/s, and
b) the rate of entropy production within the duct, in kW/K if the mass flow rate of air is 0.5 kg/s