Calculate The Efficiency of Refrigeration Unit and Enthalpy State

Question

Consider the T-S diagram of a refrigerator unit. The working flid is R-22. The refrigerator operates between a low pressure of 0.60 bar absolute (measured in the evaporator) and high pressure of 18.0 bar absolute (measured in the condenser). Assume negligible pressure loss in either condenser (path 1 -> 2) or the evaporator (path 3-> 4). A throttle controls the pressure change between states 2 and 3. A perfectly insulated compressor provides the work for the cycle (Path 4->1). The quality of state 2 is 0.00 and the quality of state 4 is 1.00.

 

1) If the compressor is 100 % efficient, what is the temperature of state 1?

2) If the efficiency of the compressor was less than 100 %, the enthalpy at state 1 would be

a. Smaller
b. The same
c. Larger

than for a 100 % efficient compressor? Explain

Summary    

The question belongs to Chemical Engineering and it is about refrigeration unit. The unit operates at low pressure of 0.60 bar and high pressure of 18 bar. The questions are about whether the compressor is 100% efficient. And if the efficiency is less than 100%, the enthalpy of state 1 would be smaller, the same or larger.

Note: The solution is in handwritten format