The rear window of an automobile is defogged by passing warm air over its inner surface. If the warm air is at T; 40°C and the corresponding convection coefficient is h; = 30 W/m2.K, what are the inner and outer surface temperatures, in °C, of 4-mm-thick window glass, if the outside ambient air temperature is T = -20°C and the 0,0 associated convection coefficient is ho = 65 W/m2-K? Evaluate the properties of the glass at 300 K. Tsi i °C Ts,0 i °C

The rear window of an automobile is defogged by passing warm air over its inner surface. If the warm air is at T; 40°C and the corresponding convection coefficient is h; = 30 W/m2.K, what are the inner and outer surface temperatures, in °C, of 4-mm-thick window glass, if the outside ambient air temperature is T = -20°C and the 0,0 associated convection coefficient is ho = 65 W/m2-K? Evaluate the properties of the glass at 300 K. Tsi i °C Ts,0 i °C

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.

Chapter11: Heat Transfer By Radiation

Section: Chapter Questions

Problem 11.45P

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The rear window of an automobile is defogged by passing warm air over its inner surface. If the warm air is at T∞,i=40°C and the corresponding convection coefficient is hi=30 W/m2·K, what are the inner and outer surface temperatures, in °C, of 4-mm-thick window glass, if the outside ambient air temperature is T∞,o= -27.5°C and the associated convection coefficient is ho=65 W/m2·K? Evaluate the properties of the glass at 300 K. a. what is Ts, i in °C? b. what is Ts, o in °C?
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