Consider a room with a 1.8-m-high and 2.0-m-wide double- pane window consisting of two 4-mm-thick layers of glass separated by a 10-mm-wide stagnant air space. The convection heat transfer coefficients on the inner and outer surfaces of the window are 12 W/m? K and 25 W/m? K, respectively, while the average thermal conductivity of glass is 0.78 W/m K; and the air, 0.026 W/m K. If the room is maintained at 22C. the outside temperature is -4 °C and heat transfer due to radiation can be neglected, determine: (i) Draw the sketch and thermal resistance network: (ii) the total thermal resistance; (iii) the steady rate of heat transfer through this double-pane window (iv) the temperature of the inner surface of the window.

Consider a room with a 1.8-m-high and 2.0-m-wide double- pane window consisting of two 4-mm-thick layers of glass separated by a 10-mm-wide stagnant air space. The convection heat transfer coefficients on the inner and outer surfaces of the window are 12 W/m? K and 25 W/m? K, respectively, while the average thermal conductivity of glass is 0.78 W/m K; and the air, 0.026 W/m K. If the room is maintained at 22C. the outside temperature is -4 °C and heat transfer due to radiation can be neglected, determine: (i) Draw the sketch and thermal resistance network: (ii) the total thermal resistance; (iii) the steady rate of heat transfer through this double-pane window (iv) the temperature of the inner surface of the window.

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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