An air-standard cycle is executed within a closed piston-cylinder system and consists of three processes as follows:

Question:

An air-standard cycle is executed within a closed piston-cylinder system and consists of three processes as follows:
1-2 V = constant heat addition from 100 kPa and 27oC to 700 kPa
2-3 Isothermal expansion until V3 = 7V2
3-1 P = constant heat rejection to the initial state Assume air has constant properties with cv = 0.718 kJ/kg·K, cp = 1.005 kJ/kg·K, R = 0.287 kJ/kg·K, and k = 1.4.
(a) Sketch the P-v and T-s diagrams for the cycle.
(b) Determine the ratio of the compression work to the expansion work (the back work ratio).
(c) Determine the cycle thermal efficiency.