12-37 Two concentric spheres of diameters D₁ = 0.3 m and D₂ = 0.8 m are maintained at uniform temperatures T₁ = 700 K and T₂ = 400 K and have emissivities &₁ = 0.5 and &2 = 0.7, respectively. Determine the net rate of radiation heat transfer between the two spheres. Also, determine the convec- tion heat transfer coefficient at the outer surface if both the sur- rounding medium and the surrounding surfaces are at 30°C. Assume the emissivity of the outer surface is 0.35.

12-37 Two concentric spheres of diameters D₁ = 0.3 m and D₂ = 0.8 m are maintained at uniform temperatures T₁ = 700 K and T₂ = 400 K and have emissivities &₁ = 0.5 and &2 = 0.7, respectively. Determine the net rate of radiation heat transfer between the two spheres. Also, determine the convec- tion heat transfer coefficient at the outer surface if both the sur- rounding medium and the surrounding surfaces are at 30°C. Assume the emissivity of the outer surface is 0.35.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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