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An ideal vapour refrigeration cycle uses RF-134a as the working fluid and consists of the following...

An ideal vapour refrigeration cycle uses RF-134a as the working fluid and consists of the following steps:

(i) Saturated vapour at 20 psia is compressed adiabatically and reversibly to a pressure of 120 psia. [The compressor]

(ii) The vapour is cooled and condensed at constant pressure, leaving the condenser as a saturated liquid. [The condenser]

(iii) The saturated liquid is expanded through a throttling valve to a pressure of 20 psia. [The throttling valve]

(iv) The liquid-vapour mixture leaving the throttling valve is heated at constant pressure until it is 100% saturated vapour. [The evaporator]

The flow rate of refrigerant in this cycle is 0.1 kg s^-1. For this cycle do the following:

(a) Plot the cycle on the attached P-h chart for RF-134a.

(b) Calculate the power input to the compressor in kW.

(c) Calculate the heat transferred to the environment in the condenser in kW.

(d) Calculate the coefficient of performance (as a refrigerator) for the cycle. (5marks)

Total = 20 marks

Note: Use the attached P-H chart for R-134a as your data source.

1 kg = 2.21 lbm

1 J = 9.48*10^-4 Btu

1 bar = 10⁵ Pa = 14.5 psia

Expert Solution

Amanda K answered 6 months ago

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