Q2. The majority of houses in İzmir is equipped with air-conditioners for keeping the inside temperature of houses at comfortable levels during hot summer days. Consider a hot summer day, the outdoor temperature is 42 °C, an air-conditioner runs to keep a room at 22 °C. The room is not well-insulated and therefore absorbs heat through its walls at a rate of 400 kJ/min. There are also electronic equipments in the room generating 600 W of heat. The cooling fluid inside the air-conditioner, DuPont™ Freon 12 enters into the compressor as a saturated vapor at 362 kPa and leaves it at 1000 kPa and 60 °C. The fluid flow rate through the compressor is 6000 L/h. а. What is the actual coefficient of performance of the air-conditioner? b. What is the minimum power input to the compressor for the same refrigeration process.

Q2. The majority of houses in İzmir is equipped with air-conditioners for keeping the inside temperature of houses at comfortable levels during hot summer days. Consider a hot summer day, the outdoor temperature is 42 °C, an air-conditioner runs to keep a room at 22 °C. The room is not well-insulated and therefore absorbs heat through its walls at a rate of 400 kJ/min. There are also electronic equipments in the room generating 600 W of heat. The cooling fluid inside the air-conditioner, DuPont™ Freon 12 enters into the compressor as a saturated vapor at 362 kPa and leaves it at 1000 kPa and 60 °C. The fluid flow rate through the compressor is 6000 L/h. а. What is the actual coefficient of performance of the air-conditioner? b. What is the minimum power input to the compressor for the same refrigeration process.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.46P

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