Consider 469 mm × 447 mm window in an aircraft. For a temperature difference of 98°C from the inner to the outer surface of the window, calculate the heat loss rate through L = 15-mm-thick polycarbonate, soda lime glass, and aerogel windows, respectively. The thermal conductivities of the soda lime glass, aerogel and polycarbonate are ksl = 1.960 W/m, kag = 0.011 W/m · K and kpc = 0.201 W/m · K, respectively. If the aircraft has 110 windows and the cost to heat the cabin air is $1.8/kW · h, compare the costs associated with the heat loss through the windows for an 10-hour intercontinental flight

Consider 469 mm × 447 mm window in an aircraft. For a temperature difference of 98°C from the inner to the outer surface of the window, calculate the heat loss rate through L = 15-mm-thick polycarbonate, soda lime glass, and aerogel windows, respectively. The thermal conductivities of the soda lime glass, aerogel and polycarbonate are ksl = 1.960 W/m, kag = 0.011 W/m · K and kpc = 0.201 W/m · K, respectively. If the aircraft has 110 windows and the cost to heat the cabin air is $1.8/kW · h, compare the costs associated with the heat loss through the windows for an 10-hour intercontinental flight

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 1.1P: 1.1 On a cold winter day, the outer surface of a 0.2-m-thick concrete wall of a warehouse is exposed...

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Question 1: A glass window of width W = 1 m and height H = 2m is 5 mm thick and has a thermal conductivity of kg =1.4 W/m.K. If the inner and outer surface temperatures of the glass are 15 °C and -20 C, respectively, on a cold winter day, what is the rate of heat loss through the glass? To reduce heat loss through windows, it is customary to use a double pane construction in which adjoining panes are separated by an air space. If the spacing is 10 mm and the glass surfaces in contact with the air have temperatures of (last two digit of your Registration number) °C and -15 °C, what is the rate of heat loss from a 1 mx2mwindow? The thermal conductivity of air is ka = 0.024 W/m.K.
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