You have to do thermal analysis of a building near an arctic observatory, which has a footprint of 8-mx12-m and height of 4-m and oriented as shown. Because the wind direction and velocities are different on each side wall, the convection coefficient for each wall and roof are different. They are as follows h North = 5 W/m².K, South 15 W/m².K, hEast = 24 W/m².K, West = 12 W/m².K, and Roof 30 W/m².K, where the subscript ndicate the corresponding wall/roof (for example, North is the convection coefficient for the North-facing wall). The ambient air temperature is -15°C. The sky temperature is -20°C. The solar irradiation is 350 W/m², which can be considered to be falling only on the roof and not on the walls. The surface temperature of the building is 10°C. Neglect heat transfer through the ground. What is the total heat transfer to/from the building? s the building losing or gaining heat? What is the dominant mode of heat transfer? What is the ratio between the heat transfer rates through the roof and through the North wall? The solar absorptivity is 0.8, the emissivity of the wall and roof is 0.7. = = Total: 121463W from bldg It is losing heal 8 Dominant Convection Ralis: 5.18 12 m SOUTH NORTH

You have to do thermal analysis of a building near an arctic observatory, which has a footprint of 8-mx12-m and height of 4-m and oriented as shown. Because the wind direction and velocities are different on each side wall, the convection coefficient for each wall and roof are different. They are as follows h North = 5 W/m².K, South 15 W/m².K, hEast = 24 W/m².K, West = 12 W/m².K, and Roof 30 W/m².K, where the subscript ndicate the corresponding wall/roof (for example, North is the convection coefficient for the North-facing wall). The ambient air temperature is -15°C. The sky temperature is -20°C. The solar irradiation is 350 W/m², which can be considered to be falling only on the roof and not on the walls. The surface temperature of the building is 10°C. Neglect heat transfer through the ground. What is the total heat transfer to/from the building? s the building losing or gaining heat? What is the dominant mode of heat transfer? What is the ratio between the heat transfer rates through the roof and through the North wall? The solar absorptivity is 0.8, the emissivity of the wall and roof is 0.7. = = Total: 121463W from bldg It is losing heal 8 Dominant Convection Ralis: 5.18 12 m SOUTH NORTH

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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