k (glass) = 1.4 W/m-K, from Table A.3 k (air) = 0.0239 W/m-K, from Table A.4, property evaluated @ 270 K 1. A 0.75-m x 1.5-m window is constructed of 6-mm-thick glass. On a cold night, the inside and outside surface temperatures of the glass are 16°C and -24°C, respectively. (a) What is the rate of heat loss through the glass? (b) The window is replaced by a double-paned window, in which two panes of glass are separated by an air space. If the spacing of the panes is 13 mm and the glass surface temperatures in contact with the interior air space are 12°C and -18°C, what is the new rate of heat loss from the window? (Hint: since the temperatures on the inside glass surfaces are given, you need only analyze conduction across the air gap.)

k (glass) = 1.4 W/m-K, from Table A.3 k (air) = 0.0239 W/m-K, from Table A.4, property evaluated @ 270 K 1. A 0.75-m x 1.5-m window is constructed of 6-mm-thick glass. On a cold night, the inside and outside surface temperatures of the glass are 16°C and -24°C, respectively. (a) What is the rate of heat loss through the glass? (b) The window is replaced by a double-paned window, in which two panes of glass are separated by an air space. If the spacing of the panes is 13 mm and the glass surface temperatures in contact with the interior air space are 12°C and -18°C, what is the new rate of heat loss from the window? (Hint: since the temperatures on the inside glass surfaces are given, you need only analyze conduction across the air gap.)

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.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.31P: A spherical communications satellite, 2 m in diameter, is placed in orbit around the earth. The...

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