A heating system must maintain the interior of a building at 16°C during a period when the outside air temperature is 5°C and the heat transfer from the building through its roof and walls is 3 x 106 kJ. For this duty heat pumps are under consideration that would operate between the dwelling and: (a) the ground at 15°C. (b) a pond at 10°C. (c) the outside air at 5°C. For each case, evaluate the minimum theoretical net work input required by any such heat pump, in kJ. Part A For case (a), evaluate the minimum theoretical net work input required by any such heat pump, in kJ. (Wcycle) min kJ

A heating system must maintain the interior of a building at 16°C during a period when the outside air temperature is 5°C and the heat transfer from the building through its roof and walls is 3 x 106 kJ. For this duty heat pumps are under consideration that would operate between the dwelling and: (a) the ground at 15°C. (b) a pond at 10°C. (c) the outside air at 5°C. For each case, evaluate the minimum theoretical net work input required by any such heat pump, in kJ. Part A For case (a), evaluate the minimum theoretical net work input required by any such heat pump, in kJ. (Wcycle) min kJ

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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