Problem 1. Consider a 0.8-meter-high and 1.5-meter-wide double-pane window consisting of two 4-mm-thick layers of glass (k = 0.78 W/m-K) separated by a 10-mm-wide stagnant air space (k = 0.026 W/m-K), as shown in Fig. 1. The room temperature is maintained at T; = 20°C, while the temperature of the outdoors is To = -10°C. Assume that the convection heat transfer coefficients on the inner and outer surfaces of the window are h₂ = 10 W/m²-K and ho= 40 W/m²-K. (a) Sketch the thermal resistance network of the problem and calculate the in- dividual thermal resistances. (b) Determine the steady-state rate of heat transfer through the double-pane window. (c) Calculate the temperature at the window's inner surface (facing the room).

Problem 1. Consider a 0.8-meter-high and 1.5-meter-wide double-pane window consisting of two 4-mm-thick layers of glass (k = 0.78 W/m-K) separated by a 10-mm-wide stagnant air space (k = 0.026 W/m-K), as shown in Fig. 1. The room temperature is maintained at T; = 20°C, while the temperature of the outdoors is To = -10°C. Assume that the convection heat transfer coefficients on the inner and outer surfaces of the window are h₂ = 10 W/m²-K and ho= 40 W/m²-K. (a) Sketch the thermal resistance network of the problem and calculate the in- dividual thermal resistances. (b) Determine the steady-state rate of heat transfer through the double-pane window. (c) Calculate the temperature at the window's inner surface (facing the room).

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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