It is cooled by passing air over the glass plate at 600°C. The heat transfer coefficient is 5 W/ m²K. It is known that the temperature at any point in the glass during the cooling process should not exceed 15°C /mm in order to prevent cracking. If the glass heat transfer coefficient is 1.4 w/mk and the emissivity of the surface is 0.8, what is the lowest air temperature that can be used for cooling at the start-up time? Assume that the air temperature is equal to the temperature of the surrounding surfaces

It is cooled by passing air over the glass plate at 600°C. The heat transfer coefficient is 5 W/ m²K. It is known that the temperature at any point in the glass during the cooling process should not exceed 15°C /mm in order to prevent cracking. If the glass heat transfer coefficient is 1.4 w/mk and the emissivity of the surface is 0.8, what is the lowest air temperature that can be used for cooling at the start-up time? Assume that the air temperature is equal to the temperature of the surrounding surfaces

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.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.32P

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