A piston-cylinder device has an initial contained volume of 0.1 ft3 and contains steam at an initial state of 160 psia, 500°F. The steam is then expanded to 20 psia, 0.65 ft3 and as a result of this process 0.50 Btu of heat is transferred to the system. Assume that the atmospheric conditions are 14.7 psia and 80°F.
a. Find the actual useful work done by the system.
b. Find the change in availability during the process.
c. What is the second law efficiency of the process?