In: Mechanical Engineering
A piston-cylinder device initially has a volume of 1.5 m3 containing steam at 300 kPa absolute and 150 oC. It is then heated so it expands at constant pressure until it reaches a temperature of 400 oC.
Draw a diagram of the device showing system boundary and flows of energy. What boundary work is done by the cylinder, in kJ, during the expansion? State your assumptions.
1. What is the mass of steam in the piston-cylinder?
2. How much heat is added to the cylinder, in kJ, during the expansion? State your assumptions.
3. Assuming there are no irreversibilities during the expansion; S.GEN=0, does the entropy of the steam decrease, remain constant, or increase during the expansion? Explain your answer.