A square window of side 1 m with a glass thickness of 1 cm looks out onto a frosty scene at a temperature of 0 C. The other side of the glass is at 20 C. Calculate the rate of heat transfer through the window by a. Conduction b. Radiation c. Calculate the rate of heat transfer by conduction only through a similarly sized portion of air i.e. 1 cm thick and with area 1 m2 Compare your answer to that in part (a) above and hence describe the advantage of double glazing. Assume the coefficient of thermal conductivities for glass and air are 0.96 Wm/K and 0.03 Wm/K respectively, that the emissivity is 1.0 and that the glass is perfectly transmitting at all wavelengths.

A square window of side 1 m with a glass thickness of 1 cm looks out onto a frosty scene at a temperature of 0 C. The other side of the glass is at 20 C. Calculate the rate of heat transfer through the window by a. Conduction b. Radiation c. Calculate the rate of heat transfer by conduction only through a similarly sized portion of air i.e. 1 cm thick and with area 1 m2 Compare your answer to that in part (a) above and hence describe the advantage of double glazing. Assume the coefficient of thermal conductivities for glass and air are 0.96 Wm/K and 0.03 Wm/K respectively, that the emissivity is 1.0 and that the glass is perfectly transmitting at all wavelengths.

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.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.60P

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Heat transfer