A small, thin metal plate of area A m² is kept insulated on one side and exposed to the sun on the other. The plate absorbs solar energy at a rate of 500 W/m“. It dissipates heat by convection to the ambient air at Ta = 300 K with a convection heat transfer coefficient of 20 W/m K, and by radiation into the sky, which may be assumed to be a black body with a temperature of 280 K. The emissivity of the plate is e = 0.92. Determine the equilibrium temperature of the plate, and the proportions of energy dissipated by convection and by radiation. (Hint: you will need to find the temperature of the plate by iteration.)

A small, thin metal plate of area A m² is kept insulated on one side and exposed to the sun on the other. The plate absorbs solar energy at a rate of 500 W/m“. It dissipates heat by convection to the ambient air at Ta = 300 K with a convection heat transfer coefficient of 20 W/m K, and by radiation into the sky, which may be assumed to be a black body with a temperature of 280 K. The emissivity of the plate is e = 0.92. Determine the equilibrium temperature of the plate, and the proportions of energy dissipated by convection and by radiation. (Hint: you will need to find the temperature of the plate by iteration.)

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 11.32P

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