The outer surface of a spacecraft in space has an emissivity of ε=0.8 and a solar absorptivityof a = 0.3. Solar radiation is incident on the spacecraft at a rate of 950 W/m². Determine the surfacetemperature of the spacecraft when the radiation emitted equals the solar energy absorbed.950 W/m2a= 0.3c=0.8Qrad

Answered: The outer surface of a spacecraft in…

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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Determine the rate of radiant heat emission in watts per square meter from a blackbody at (a) 15C, (b) 600C, and (c) 5700C.
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A particular furnace is shaped like a section of a cone. The top surface of the furnace is uniformly heated by a resistance heater. During operation, the top surface is measured to be 800 K and the power supplied to the resistance heater is 1750 W/m². The sidewall of the furnace is perfectly insulated with & = 0.2. If the emissivity of the top and bottom surfaces are ε = 0.5 and ε = 0.7, respectively, determine the temperatures of the sidewall and the bottom surface of the furnace. A₁ A2 A3 →→D₂ = 20 mm D₁ = 40 mm L = 50 mm
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