Consider a 1.2-m-high and 2-m-wide glass windowwith a thickness of 6 mm, thermal conductivity k = 0.78W/m·K, and emissivity « = 0.9. The room and the wallsthat face the window are maintained at 25°C, and the averagetemperature of the inner surface of the window is measuredto be 5°C. If the temperature of the outdoors is 25°C,determine (a) the convection heat transfer coefficient on theinner surface of the window, (b) the rate of total heat transferthrough the window, and (c) the combined natural convectionand radiation heat transfer coefficient on the outer surface ofthe window. Is it reasonable to neglect the thermal resistanceof the glass in this case?

Consider a 1.2-m-high and 2-m-wide glass windowwith a thickness of 6 mm, thermal conductivity k = 0.78W/m·K, and emissivity « = 0.9. The room and the wallsthat face the window are maintained at 25°C, and the averagetemperature of the inner surface of the window is measuredto be 5°C. If the temperature of the outdoors is 25°C,determine (a) the convection heat transfer coefficient on theinner surface of the window, (b) the rate of total heat transferthrough the window, and (c) the combined natural convectionand radiation heat transfer coefficient on the outer surface ofthe window. Is it reasonable to neglect the thermal resistanceof the glass in this case?

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.

Chapter6: Forced Convection Over Exterior Surfaces

Section: Chapter Questions

Problem 6.4P: An electrical transmission line of 1.2-cm diameter carries a current of 200 amps and has a...

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