Sample Test #3
Problem 2: A cylinder/piston assembly contains 1 kg of air undergoes a thermodynamic cycle consisting of the following three reversible processes in series. The initial volume of the assembly is unknown. R=0.287(kJ/kg K), Cp=1.003(kJ/kgK), Cv=0.717(kJ/kgK), k=Cp/Cv=1.4
- Process 1-2: isothermal compression from P1=0.1 MPa to P2=0.5 Mpa
- Process 2-3: constant pressure expansion to T3=400 K
- Process 3-1: adiabatic expansion to the initial state
Using the ideal gas model and Tds equation,
(a) sketch the cycle on P-v and T-s diagrams
(b) determine the net work done by the system
(c) determine the net heat transfer into the system