t is intended to reduce heat losses of a glass window (k = 1.4 W/m.K) with 6 mm thick, covering it with a polystyrene insulation (k = 0.027 W/(m.K) with 25 mm thickness. The contact resistance between the glass and the insulation is estimated at 0.002 m². K/W, while the heat transfer coefficient by convection of the outer surface of the window is worth he = 20 W/(m². K). With insulation, the convection heat transfer coefficient in the inner wall is hi = 2 W/m². K; no insulation is hi = 5 W/m². K. If the total surface area of the window is A = 12 m², what are the heat losses associated with insulated and non-insulated window for indoor and outdoor air temperatures Ti= 20 ºC and Te = – 12 ºC

t is intended to reduce heat losses of a glass window (k = 1.4 W/m.K) with 6 mm thick, covering it with a polystyrene insulation (k = 0.027 W/(m.K) with 25 mm thickness. The contact resistance between the glass and the insulation is estimated at 0.002 m². K/W, while the heat transfer coefficient by convection of the outer surface of the window is worth he = 20 W/(m². K). With insulation, the convection heat transfer coefficient in the inner wall is hi = 2 W/m². K; no insulation is hi = 5 W/m². K. If the total surface area of the window is A = 12 m², what are the heat losses associated with insulated and non-insulated window for indoor and outdoor air temperatures Ti= 20 ºC and Te = – 12 ºC

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.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.38P: 2.38 The addition of aluminum fins has been suggested to increase the rate of heat dissipation from...

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