An air-standard cycle is executed within a closed piston–cylinder system, and it consists of the following three processes:
1–2 v = constant heat addition from 100 kpa and 38°c to 850 kpa
2–3 isothermal expansion until v3 = 8.5v2
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.)determine the ratio of the compression work to the expansion work (the back work ratio).
b.)determine the cycle thermal efficiency