Question

An air conditioner of 2-ton capacity used R134a as a refrigerant fluid and operates between 0oC and 44oC. Assuming simple saturation cycle which has two cylinders, the compressor has a Bore and Stroke 5.65 and 5 cm respectively, it is speed 1450 rpm and volumetric efficiency ??.? = 100% , determine: (a) The (COP) of the cycle and piston displacement. (b) If the same conditioner is used for heating in winter and operating in the temperature range of -5 oC and 55oC, find the performance factor (PF) of the heat pump for heating purpose and its heating capacity in kW. (c). Find the single phase electric power required to run the compressor in summer as well as in winter. (d) Find its new (COP) and heat capacity, If the overall efficiency of the compressor will be 0.88.

Answer 1

in part d, for summer Air conditioning only compressor work changes, refrigerating effect remains same, hence multiplied by 0.88.

For winter air conditioning h2 changes , hence heat capacity and compressor work both are affected, hence recalculated.