Question

In: Mechanical Engineering

Air within a piston cylinder assembly executes a Carnot refrigeration cycle between hot and cold reservoirs...

Air within a piston cylinder assembly executes a Carnot refrigeration cycle between hot and cold reservoirs at TH=500 K and TC=300 K, respectively. The magnitude of the heat transfer rejected to the high temperature reservoir is 250 kJ per kg of air. The pressure at the start of the isothermal expansion is 325 kPa. The air can be modeled as an ideal gas with constant specific heat.
For the air as a system, determine
a. (5) the coefficient of performance.
b. (5) the net work input to the cycle in kJ/kg.
c. (10) the Pv and Ts diagrams for the cycle with arrows showing the directions of the processes.

Solutions

Expert Solution

a) answer- 1.5

B) answer - 100KJ/kg of air


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