With increasing emphasis on energy conservation, the heat loss from buildings has become a major concern. For a small tract house the typical exterior surface areas and R-factors (area x thermal resistance) are listed below Element Area (m²) R-Factors = Area > Thermal Resistance [(m² K/W)] 2.0 2.8 Walls Ceiling Floor Windows Doors 150 120 120 20 5 2.0 0.1 0.5 (a) Calculate the rate of heat loss from the house when the interior temperature is 22°C and the exterior is -5°C. (b) Suggest ways and means to reduce the heat loss and show quantitatively the effect of doubling the wall insulation and the substitution of double glazed windows (thermal resistance = 0.2 m² K/W) for the single glazed type in the table above.

With increasing emphasis on energy conservation, the heat loss from buildings has become a major concern. For a small tract house the typical exterior surface areas and R-factors (area x thermal resistance) are listed below Element Area (m²) R-Factors = Area > Thermal Resistance [(m² K/W)] 2.0 2.8 Walls Ceiling Floor Windows Doors 150 120 120 20 5 2.0 0.1 0.5 (a) Calculate the rate of heat loss from the house when the interior temperature is 22°C and the exterior is -5°C. (b) Suggest ways and means to reduce the heat loss and show quantitatively the effect of doubling the wall insulation and the substitution of double glazed windows (thermal resistance = 0.2 m² K/W) for the single glazed type in the table above.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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