1) Given: Nitrogen (N2) gas within a piston-cylinder assembly undergoes a compression from P1 = 0.2 MPa, V1 = 2.75 m3 to a state where P2 = 1.5 MPa. The relationship between pressure and volume during the process is PV1.35 = C.
Find: a) Sketch the process on a P-V diagram and label work in the diagram, b) calculate the final volume, and c) calculate the work (kJ) for the process.
2) Given: Air contained within a piston-cylinder assembly undergoes three processes in series.
Process 1-2: Compression at constant pressure from P1 = 10 lbf/in2, V1 = 4 ft3 to state 2.
Process 2-3: Constant volume heating to state 3, where P3 = 50 lbf/in2.
Process 3-1: Expansion to the initial state, during which PV = constant.
Find: a) Sketch all 3 processes on P-V axes. Evaluate b) V2 and c) the work for each process (Btu). Hint: You need to establish state 3 in order to find state 2.
3) Given: Steam contained within a piston-cylinder assembly undergoes an expansion from state 1, where u1 = 2709.9 kJ/kg, to state 2, where u2 = 2659.6 kJ/kg. During the process, there is heat transfer of 80 kJ to the steam. Also, a paddle wheel transfers 18.5 kJ of energy to the steam by work. There is no significant change in kinetic or potential energy of the steam.
Find: The energy transfer by work from the steam to the piston during the process (kJ).