3. A) Propane enters a turbine at 20 bar, 110°C and exits at 2 bar, 50°C. Heat losses to the
surroundings are 15% of the power generated. Neglect kinetic and potential energy effects.
What is the work output of the turbine in kJ/kg of propane for steady state operation?
B) What is the specific entropy change of the propane for part A)?
C) If the turbine in part A) were to operate adiabatically and reversibly (or in other words
isentropically), what would the value of the exit entropy be?
D) For the same inlet and exit conditions as for part A), if the heat losses were eliminated,
would the turbine output be greater than, less than, or the same as in part A (no calculations
needed)?
E) For operation of any real turbine, is entropy production positive, negative, or zero (no
calculations needed)?
