A room is kept at - 5oC by a vapor-compression refrigeration cycle with R-134a as the refrigerant. Heat is rejected to cooling water that enters the condenser at 20oC at a rate of 0.13 kg/s and leaves at 28oC. The refrigerant enters the condenser at 1.2 MPa and 50oC and leave as a saturated liquid. If the compressor consumes 1.9 kW of power, determine
(a) The refrigeration load, in Btu/h and the COP.
(b) The second-law efficiency of the refrigerator and the total exergy destruction in the cycle.
(c) The exergy destruction in the condenser. Take T0 = 20oC and cp, water = 4.18 kJ/kg·osC.

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Water 20 C 28°C 0.13 kg/s 1.2 MPa sat. liquid 1.2 MPa 50°C Condenser Expansion valve Compressor Evaporator 0