Plate glass 5 mm thick at 200Â\deg C is to be cooled from both sides using air at 40Â\deg C. If surface cracks are to be avoided, determine the maximum value of convective heat transfer coefficient. Material properties are density = 2500 kg/mÂ ^3, specific heat = 670 J/kgK, and thermal conductivity = 0.744 W/mK. Also, determine the time required to cool the plate to 80Â\deg C.

Plate glass 5 mm thick at 200Â\deg C is to be cooled from both sides using air at 40Â\deg C. If surface cracks are to be avoided, determine the maximum value of convective heat transfer coefficient. Material properties are density = 2500 kg/mÂ ^3, specific heat = 670 J/kgK, and thermal conductivity = 0.744 W/mK. Also, determine the time required to cool the plate to 80Â\deg 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.

Chapter7: Forced Convection Inside Tubes And Ducts

Section: Chapter Questions

Problem 7.29P

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