1. Air at 600 kPa, 330 K enters a well-insulated, horizontal pipe having a diameter of 1.2 cm and exits at 120 kPa, 300 K. Applying the ideal gas model for air, determine at steady state (a) the inlet and exit velocities, each in m/s, (b) the mass flow rate, in kg/s, and (c) the rate of entropy production, in kW/K.
2. At steady state, air at 200 kPa, 528C and a mass flow rate of 0.5 kg/s enters an insulated duct having differing inlet and exit cross-sectional areas. At the duct exit, the pressure of the air is 100 kPa, the velocity is 255 m/s, and the cross-sectional area is 2 3 1023 m2. Assuming the ideal gas model, determine
(a) the temperature of the air at the exit, in 8C.
(b) the velocity of the air at the inlet, in m/s.
(c) the inlet cross-sectional area, in m2.
(d) the rate of entropy production within the duct, in kW/K.