3- A building wall consists of 25 cm concrete (K= 1.75 W/m.K) and 1.9 cm plaster (K= 87 W/m.K) on the inside surface. The outside temperature is -18°C, while the room is held at 23.5°C DBT and 16.8°C WBT. (a) What is the temperature on the inside wall surface. (b) Will the moisture condense on the wall. (c) How many layers of 1.25 cm thick fiber-board insulation (K= 0.048 W/m.K) should be applied on the inside wall surface to prevent moisture to condense on it.

3- A building wall consists of 25 cm concrete (K= 1.75 W/m.K) and 1.9 cm plaster (K= 87 W/m.K) on the inside surface. The outside temperature is -18°C, while the room is held at 23.5°C DBT and 16.8°C WBT. (a) What is the temperature on the inside wall surface. (b) Will the moisture condense on the wall. (c) How many layers of 1.25 cm thick fiber-board insulation (K= 0.048 W/m.K) should be applied on the inside wall surface to prevent moisture to condense on it.

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.

Chapter3: Transient Heat Conduction

Section: Chapter Questions

Problem 3.17P: 3.17 A 1.4-kg aluminum household iron has a 500-W heating element. The surface area is . The ambient...

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