Question: 2 ) ( 3 5 points ) A vapor - compression refrigerator uses two stages of compression and flash intercooling as a means of reducing

2)(35 points) A vapor-compression refrigerator uses two stages of compression and flash intercooling as a means of reducing total compression work. On the next two pages, a description of the process, taken from section 10.4.3 in Moran and Shapiro, is attached. The refrigerator has a cooling capacity of 70 kW . The condenser pressure is 1 MPa , while the direct contact heat exchanger and flash chamber are at 0.5 MPa . Saturated liquid at 1 MPa exits the condenser while saturated vapor at \(-20^{\circ}\mathrm{C}\) exits the evaporator. Saturated liquid at 0.5 MPa enters the expansion valve below the flash chamber. The refrigerant is R-22; assume that both compressors are isentropic.
A) What is the quality of the two-phase mixture separated in the flash chamber.
B) What is the mass flow rate (\(\mathrm{kg}/\mathrm{s}\)) of R-22 through the evaporator?
C) What is the mass flow rate (\(\mathrm{kg}/\mathrm{s}\)) of R-22 through the condenser?
D) What is the power ( kW ) required to run the first compressor stage (immediately downstream of the evaporator)? Note that two-parameter interpolation is required to find the outlet state of the first compressor stage.
E) What is the power (kW) required to run the second compressor stage? Hint: To find the inlet state state 3 in Fig. 10.10- an energy balance must be carried out on the direct contact heat exchanger.
F) What is the refrigerator's coefficient of performance?
2 ) ( 3 5 points ) A vapor - compression

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