文档介绍：Thermal Energy Problem Set #5– Fall 2002
Time spent on problems:
Problem 1:
Problem 2:
Problem 3:
Problem 4:
Problem 5:
Problem 6:
Thermal Energy Problem Set #5 – Fall 2002
Do all problems. Please use a separate sheet of paper for each problem.
1. Air is to pressed from atmospheric pressure at 290 K to 7 atm in a centrifugal
compressor (isentropic efficiency about ). The flow rate will be kg/s.
Specify the power requirement for the driving motor. You may assume the working
fluid is a perfect gas with cp=1 kJ/kgK.
2. Air enters an adiabatic nozzle at 800 K and 140 kPa and emerges at 7 kPa. The
isentropic efficiency of the nozzle is known to be . Determine the discharge
velocity. Sketch the process on a T-s diagram and label the states. You may assume
the working fluid is a perfect gas with cp=1 kJ/kgK.
3. An inventor has developed a method to run a Carnot cycle, as shown in the figure
below, between two temperatures, TH and TL. The rate of heat removed from the
high temperature source is QH . The only drawback is that there is a small leak so
that a quantity of heat, QLeak , per second “leaks” through the engine from the high
temperature heat source to the low temperature heat sink.
TH
QH
QLeak W = ?
QL = ?
TL
a) What is the power produced by the leaky Ca