A cylindrical cold storage facility with an inner diameter of 4m and height of 2m is constructed. For the wall, the first layer is 6 cm of glass wool (0.1 W/m-C), followed by 30 cm of concrete. The temperature inside is maintained at -10C (hin = 55 W/m^2-C) while the outside temperature is 10°C (hout = 22 w/m^2-C). If the steady rate of heat transfer is at 60W, (a) what is the thermal conductivity of concrete? (b) At what radius is the temperature at 0°C? To prevent water condensation inside the concrete wall (which damages the structure), A 5 cm layer of insulation (k = 0.15 W/m-C) is added to the exterior of the facility. (c) What is the new rate of heat transfer? (d) What is the temperature at the interface of the concrete wall and new insulation? (e) is condensation within the core of the wall prevented?

A cylindrical cold storage facility with an inner diameter of 4m and height of 2m is constructed. For the wall, the first layer is 6 cm of glass wool (0.1 W/m-C), followed by 30 cm of concrete. The temperature inside is maintained at -10C (hin = 55 W/m^2-C) while the outside temperature is 10°C (hout = 22 w/m^2-C). If the steady rate of heat transfer is at 60W, (a) what is the thermal conductivity of concrete? (b) At what radius is the temperature at 0°C? To prevent water condensation inside the concrete wall (which damages the structure), A 5 cm layer of insulation (k = 0.15 W/m-C) is added to the exterior of the facility. (c) What is the new rate of heat transfer? (d) What is the temperature at the interface of the concrete wall and new insulation? (e) is condensation within the core of the wall prevented?

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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