A vapor compression refrigerator using R134a as the refrigerant operates under the following conditions: The refrigerant...

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A vapor compression refrigerator using R134a as the refrigerant operates under the following conditions: The refrigerant condenses at 50C and is then sub-cooled by 10C to 30C before expansion. After an isenthalpic expansion, the refrigerant evaporates at -20C and then superheated by 10C to 0C before compression. The refrigerant is compressed to 70C with entropy of 1.0 kJ/kgK at the end of the compression. a)With reference to the above operating conditions, draw the cycle on the R134a p-h diagram. b)Calculate the specific refrigerating effect at the evaporating temperature of -20C. c)Calculate the work input for the compression process. d)Prove the vapor compression is not an isentropic process. e)Calculate the COP of the cycle. f)To produce 5kW cooling, what is the refrigerant flow rate required? A vapor compression refrigerator using R134a as the refrigerant operates under the following conditions: The refrigerant condenses at 50C and is then sub-cooled by 10C to 30C before expansion. After an isenthalpic expansion, the refrigerant evaporates at -20C and then superheated by 10C to 0C before compression. The refrigerant is compressed to 70C with entropy of 1.0 kJ/kgK at the end of the compression. a)With reference to the above operating conditions, draw the cycle on the R134a p-h diagram. b)Calculate the specific refrigerating effect at the evaporating temperature of -20C. c)Calculate the work input for the compression process. d)Prove the vapor compression is not an isentropic process. e)Calculate the COP of the cycle. f)To produce 5kW cooling, what is the refrigerant flow rate required?