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In: Mechanical Engineering

Air at 5 bar and 560K is expanded in steady flow in a horizontal convergent–divergent duct...

Air at 5 bar and 560K is expanded in steady flow in a horizontal convergent–divergent duct to an exit velocity
of 640 ms−1. The walls of the duct are heated so as to keep the temperature drop to one-half the value of an
isentropic expansion to the same velocity and pressure from the same initial conditions. Calculate, assuming
negligible initial velocity:
a. the heat supplied;
b. the final temperature;
c. the mass flow rate per square metre of exit area.

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