In a summer day, the outdoor air temperature is 32 C and the indoor air temperature...

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In a summer day, the outdoor air temperature is 32 °C and the indoor air temperature set-point is 23 °C. A chiller using R134a is used in the air-conditioning system of a building. The designed supply chilled water temperature is 7 °C. 6-a) If a theoretical refrigeration cycle (reversed Carnot cycle) was adopted between the indoor air temperature and outdoor air temperature, derive the theoretical maximum COP of an air- conditioning system. If the indoor air temperature is set 2 K higher (i.e. 25°C), derive the theoretical maximum COP. Calculate the COP increase in percentage. Explain briefly why the energy could be saved by increasing indoor air temperature. 6-b) If the heat and fluid transfer losses are ignored, derive the highest COP of ideal refrigeration cycle which might be achieved by the chiller. List clearly the assumptions used to arrive at each enthalpy value in the COP calculation, and mark down the states of the refrigerant in the assumed ideal refrigeration cycle. 6-c) In the real vapour compression system, the overall COP is much lower than the theoretical refrigeration cycle and the ideal refrigeration cycle. List the main reasons on why the practical COP is much lower. In a summer day, the outdoor air temperature is 32 °C and the indoor air temperature set-point is 23 °C. A chiller using R134a is used in the air-conditioning system of a building. The designed supply chilled water temperature is 7 °C. 6-a) If a theoretical refrigeration cycle (reversed Carnot cycle) was adopted between the indoor air temperature and outdoor air temperature, derive the theoretical maximum COP of an air- conditioning system. If the indoor air temperature is set 2 K higher (i.e. 25°C), derive the theoretical maximum COP. Calculate the COP increase in percentage. Explain briefly why the energy could be saved by increasing indoor air temperature. 6-b) If the heat and fluid transfer losses are ignored, derive the highest COP of ideal refrigeration cycle which might be achieved by the chiller. List clearly the assumptions used to arrive at each enthalpy value in the COP calculation, and mark down the states of the refrigerant in the assumed ideal refrigeration cycle. 6-c) In the real vapour compression system, the overall COP is much lower than the theoretical refrigeration cycle and the ideal refrigeration cycle. List the main reasons on why the practical COP is much lower.

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The questions you provided pertain to the theoretical and actual performance of refrigeration systems specifically focusing on the Coefficient of Performance COP calculations for these systems Lets ad... View the full answer