1.) Consider a sealed 20-cm-high electronic box whose base dimensions are 40 cm x40 cm placed in a vacuum chamber. The emissivity of the outer surface of the box is 0.95. If the electronic components in the box dissipate a total of 100 W of power and the outer surface temperature of the box is not to exceed 55 °C, - 40 cm 40 cm 100 W ɛ = 0.95 T = 60°C Electronic box determine the temperature at which the surrounding surfaces must be kept if this box is to be cooled by 20 cm radiation alone. Assume the heat transfer from the bottom surface of Stand the box to the stand to be negligible.

1.) Consider a sealed 20-cm-high electronic box whose base dimensions are 40 cm x40 cm placed in a vacuum chamber. The emissivity of the outer surface of the box is 0.95. If the electronic components in the box dissipate a total of 100 W of power and the outer surface temperature of the box is not to exceed 55 °C, - 40 cm 40 cm 100 W ɛ = 0.95 T = 60°C Electronic box determine the temperature at which the surrounding surfaces must be kept if this box is to be cooled by 20 cm radiation alone. Assume the heat transfer from the bottom surface of Stand the box to the stand to be negligible.

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.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.61P

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