A two-stage compression refrigeration system using refrigerant-134a as the working fluid is
considered. The fraction of the refrigerant that evaporates as it is throttled to the flash chamber, the amount
of heat removed from the refrigerated space, the compressor work, and the COP are to be determined.
Assumptions 1 Steady operating conditions exist. 2 Kinetic and potential energy changes are negligible. 3
The flashing chamber is adiabatic.
Analysis (a) The enthalpies of the refrigerant at several states are determined from the refrigerant tables to
be (Tables A-11, A-12, and A-13)