During winter, a mechanical heat pump is turned on to supply heat to a house, which is maintained at 18°C. The wall of this house is not perfectly insulated and estimated to have heat loss at a rate of 140,000 kJ/h. The house has electrical appliances that are always turn on, and generate heat at a rate of 27,000 kJ/h. Assume that the mechanical heat pump is reversible and the outdoor temperature is 2°C. List the necessary assumption, sketch the appropriate schematic to visualize the process and calculate the coefficient of performance (COP) for this mechanical heat pump.

During winter, a mechanical heat pump is turned on to supply heat to a house, which is maintained at 18°C. The wall of this house is not perfectly insulated and estimated to have heat loss at a rate of 140,000 kJ/h. The house has electrical appliances that are always turn on, and generate heat at a rate of 27,000 kJ/h. Assume that the mechanical heat pump is reversible and the outdoor temperature is 2°C. List the necessary assumption, sketch the appropriate schematic to visualize the process and calculate the coefficient of performance (COP) for this mechanical heat pump.

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.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.67P: 1.67 In beauty salons and in homes, a ubiquitous device is the hairdryer. The front end of a typical...

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