An aluminum plate 4 mm thick is mounted in a horizontal position, and its bottom surface is well insulated. A special, thin coating is applied to the top surface such that it absorbs 80% of any incident solar radiation, while having an emissivity of 0.25. The density p an specific heat c of aluminum are known to be 2700 kg/m3 and 900 J/kg-K, respectively. (a) Consider conditions for which the plate is at a temperature of 25°C and its top surface is suddenly exposed to ambient air at T = 20°C and to solar radiation that provides an incident flux of 600 W/m². The convection heat transfer coefficient between the surface and the air is h = 20 W/m2.K. What is the initial rate of change of the plate temperature, in °C/s? (b) What will be the equilibrium temperature, in °C, of the plate when steady-state conditions are reached?

An aluminum plate 4 mm thick is mounted in a horizontal position, and its bottom surface is well insulated. A special, thin coating is applied to the top surface such that it absorbs 80% of any incident solar radiation, while having an emissivity of 0.25. The density p an specific heat c of aluminum are known to be 2700 kg/m3 and 900 J/kg-K, respectively. (a) Consider conditions for which the plate is at a temperature of 25°C and its top surface is suddenly exposed to ambient air at T = 20°C and to solar radiation that provides an incident flux of 600 W/m². The convection heat transfer coefficient between the surface and the air is h = 20 W/m2.K. What is the initial rate of change of the plate temperature, in °C/s? (b) What will be the equilibrium temperature, in °C, of the plate when steady-state conditions are reached?

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 8.10P

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