Consider a vapour compression refrigeration cycle that uses R-134a as refrigerant. The R-134a enter

Consider a vapour compression refrigeration cycle that uses R-134a as refrigerant. The R-134a enters the compressor as a saturated vapour at 200 kPa, and exits the condenser as a saturated liquid at 900 kPa. The rate of refrigeration of the cycle is to be 6.0 tons of refrigeration (1 ton of refrigeration = 3.517 kW). The compressor isentropic efficiency is 80%. Determine: a) The temperature of evaporation and condensation of the refrigerant; b) Mass flow of the refrigerant R-134a, in kg/min; c) Coefficient of Performance (COP) of the refrigeration cycle. Typical vapour compression refrigeration systems use a throttling valve (or an orifice tube, or a capillary tube) to reduce the liquid refrigerant’s pressure. This is a highly irreversible process. If the cycle efficiency is to be improved by replacing the throttle with a rotary expander with 70% isentropic efficiency, d) What is the new COP? The expander delivers its work developed to the compressor.

Expert Solution

Ally Wells answered 1 year ago

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