A mechanical vapour compression refrigerator that uses R-22 as working refrigerant is referred as in Figure...

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A mechanical vapour compression refrigerator that uses R-22 as working refrigerant is referred as in Figure 1. Assume the ambient temperature (T.) and the refrigerated space temperature (TR) is 28 °C and -4 °C, respectively. Table 1 shows the thermodynamics properties of the refrigerant at each stage. The amount of heat loss during the compression process is about one-tenth of the compression work. Consider the steady flow conditions. (a) Perform energy balance analysis for each component of the system. (b) Calculate the COP of the system. (c) Conduct the entropy analysis for each component of the system. Suggest the component that should be redesigned to improve the overall system performance. State 1 2 3 4 5 6 7 Suction line Discharge line Compressor Evaporator 75 65 32 30 -10 Condenser Figure 1 Expansion valve Table 1 Temperature, Specific Enthalpy, °℃ -8 kJ/kg 402.60 407.20 456.00 445.02 238.77 236.30 236.30 To Liquid line Filter Specific entropy, kJ/(kg.K) 1.7750 1.7944 1.8304 1.7981 1.1320 1.1244 1.1392 A mechanical vapour compression refrigerator that uses R-22 as working refrigerant is referred as in Figure 1. Assume the ambient temperature (T.) and the refrigerated space temperature (TR) is 28 °C and -4 °C, respectively. Table 1 shows the thermodynamics properties of the refrigerant at each stage. The amount of heat loss during the compression process is about one-tenth of the compression work. Consider the steady flow conditions. (a) Perform energy balance analysis for each component of the system. (b) Calculate the COP of the system. (c) Conduct the entropy analysis for each component of the system. Suggest the component that should be redesigned to improve the overall system performance. State 1 2 3 4 5 6 7 Suction line Discharge line Compressor Evaporator 75 65 32 30 -10 Condenser Figure 1 Expansion valve Table 1 Temperature, Specific Enthalpy, °℃ -8 kJ/kg 402.60 407.20 456.00 445.02 238.77 236.30 236.30 To Liquid line Filter Specific entropy, kJ/(kg.K) 1.7750 1.7944 1.8304 1.7981 1.1320 1.1244 1.1392