20 kg/s of air enters a 0.06 m2 duct at a pressure of

320 kPa, and a temperature of 350 K. Find the exit conditions

(pressure, temperature, and Mach number) if heat is added

to the duct at a rate of 650 kJ/kg of air.

Air enters a frictionless, constant-area duct with

p1 5 135 kPa, T1 5 500 K, and V1 5 540 m/s. How much heat

transfer is needed to choke the flow? Is the heat transfer into

or out of the duct?

Q106;

In the frictionless flow of air through a 100-mmdiameter duct, 1.42 kg/s enters at 52C and 60.0 kPa (abs).

Determine the amount of heat that must be added to choke

the flow, and the fluid properties at the choked state.