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Q10. A vapour compression refrigeration cycle using CO₂ operates between pressures of 25.0095 bar and 68.9182 bar. It produces 6 tonnes per day of ice at -8°C, from fresh water at 20°C.

The refrigerant enters the compressor as a dry saturated vapour and leaves at a temperature of 78°C, it is then condensed and enters the expansion valve as saturated liquid.

(a) Sketch the cycle on p-h and T-s diagrams.

(b) Using Datasheet Q6, determine EACH of the following:

(i) The swept volume of the compressor if the volumetric efficiency is 88%

(ii) The compressor power

(iii) The coefficient of performance of the plant.

Note: For Ice: specific heat capacity 2.1 kJ/kgK, Latent heat 335 kJ/kg

For water: specific heat capacity 4.2 kJ/kgK