Question

Steam enters a horizontal 14-cm-diameter pipe as a saturated vapor at 5 bar with a velocity of 10 m/s and exits at 4.5 bar with a quality of 95%. Heat transfer from the pipe to the surroundings at 291K takes place at an average outer surface temperature of 400 K. For operation at steady state, determine

**(a)** the velocity at the exit, in m/s.

**(b)** the rate of heat transfer from the pipe, in
kW.?

**(c)** the rate of entropy production, in kW/K,
for a control volume comprising only the pipe and its contents.

**(d)** the rate of entropy production, in kW/K,
for an enlarged control volume that includes the pipe and enough of
its immediate surroundings so that heat transfer from the control
volume occurs at 291 K.

Answer #1

Steam enters a horizontal 14-cm-diameter pipe as a saturated
vapor at 5 bar with a velocity of 10 m/s and exits at 4.5 bar with
a quality of 95%. Heat transfer from the pipe to the surroundings
at 291K takes place at an average outer surface temperature of 400
K. For operation at steady state, determine
(a) the velocity at the exit, in m/s.
(b) the rate of heat transfer from the pipe, in
kW.?
(c) the rate of entropy...

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