Consider a piston cylinder device with a volume of 0.04 m3 and initially contains air at 293 K and 1 bar.

Consider a piston cylinder device with a volume of 0.04 m³ and initially contains air at 293 K and 1 bar. It is desired to reverse the cycle and use it as a refrigerator. In this case the process would begin with PV^1.36 = constant process from an initial state of 293 K and a pressure of 10 Bars. The gas is allowed to expand to a volume 3.5 times the volume of state 1. It then follows a constant volume process in which the temperature is raised to 323 K. A constant temperature is followed back to volume 1. A constant volume process then returns it to the initial state.

a) Calculate the work input for this cycle, the heat input to the cycle that could be used to cool a space at 293 K and its coefficient of performance.

b) How much total heat is removed from the system during the cycle?

c) How much total heat input is added to the system and what fraction could be used for cooling a space that is maintained at 277K?

Expert Solution

genius_generous answered 2 years ago

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