Question

Air is heated as it flows through a constant diameter
tube. The air enters the tube at 50 psia and 80 F with an average
velocity of 10 ft/s at the entrance. The air leaves at 45 psia and
255 F.

a) Sketch the control volume

b) Determine the average velocity of the air (ft/s) at the
exit

c) If 23 lbm/min of air is to be heated, what diameter (in.) tube
is required?

Answer #1

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Helium gas enters an adiabatic nozzle at 35 psia and 820 degrees
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A piston cylinder contains 2 lbm of air and operates at a
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