A car's rear window is defogged by the passage of hot air over its inner surface. If the hot air is at T∞, i = 40 °C and the corresponding convection heat transfer coefficient is hi = 30 W/(m²K), what are the temperatures of the inner and outer surfaces of the glass, which has 4 mm thick, if the outdoor ambient air temperature for T∞, e = −10 °C and the associated convective coefficient for he = 65 W/(m²K)?

A car's rear window is defogged by the passage of hot air over its inner surface. If the hot air is at T∞, i = 40 °C and the corresponding convection heat transfer coefficient is hi = 30 W/(m²K), what are the temperatures of the inner and outer surfaces of the glass, which has 4 mm thick, if the outdoor ambient air temperature for T∞, e = −10 °C and the associated convective coefficient for he = 65 W/(m²K)?

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.

Chapter7: Forced Convection Inside Tubes And Ducts

Section: Chapter Questions

Problem 7.29P

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LTE !!:: خاص A docs.google.com Q2/ An aluminum sphere weighting 7kg and initially at a temperature of 533K is suddenly immersed in a fluid at 283K. if heat transfer coefficient between the sphere and fluid is 50W/m?.°C. Take density=2707kg/m3, specific heat=0.9KJ/kg.°C and thermal conductivity= 204W/m °C. Your answer Determine the Bi number 0.00696 0.000696 0.0052 0.00052 Other: Determine the time required to cool sphere to 263K. * 26.28min 262.8min 52.56 min 525.6 min Other: 2 Request edit access Submit
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