A refrigeration system absorbs heat from a space at 2 ◦C at a rate of 6.9 kW and rejects heat to water in the condenser. Water enters the condenser at 16 ◦C at a rate of 0.27 kg/s. The COP of the system is estimated to be 1.85. Determine (a) the power input to the system, (b) the temperature of the water at the exit of the condenser, and (c) the second-law efficiency and the exergy destruction for the refrigerator. Take the dead-state temperature to be the inlet temperature of water in the condenser. The specific heat of water is 4.18 kJ/kg· ◦C.

A refrigeration system absorbs heat from a space at 2 ◦C at a rate of 6.9 kW and rejects heat to water in the condenser. Water enters the condenser at 16 ◦C at a rate of 0.27 kg/s. The COP of the system is estimated to be 1.85. Determine (a) the power input to the system, (b) the temperature of the water at the exit of the condenser, and (c) the second-law efficiency and the exergy destruction for the refrigerator. Take the dead-state temperature to be the inlet temperature of water in the condenser. The specific heat of water is 4.18 kJ/kg· ◦C.

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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