A hollow metal sphere of outer radius or = 2 cm is heated internally with a variable output electricheater. The sphere loses heat from its surface by convection and radiation. The heat transfercoefficient is 22 W/ m2 - o C and surface emissivity is 0.92. The ambient fluid temperature is 20 o C andthe surroundings temperature is 14 oC. Construct a graph of the surface temperature corresponding toheating rates ranging from zero to 100 watts. Assume steady state. Use a simplified model forradiation exchange based on a small gray surface enclosed by a much larger surface at 14 o C.

A hollow metal sphere of outer radius or = 2 cm is heated internally with a variable output electricheater. The sphere loses heat from its surface by convection and radiation. The heat transfercoefficient is 22 W/ m2 - o C and surface emissivity is 0.92. The ambient fluid temperature is 20 o C andthe surroundings temperature is 14 oC. Construct a graph of the surface temperature corresponding toheating rates ranging from zero to 100 watts. Assume steady state. Use a simplified model forradiation exchange based on a small gray surface enclosed by a much larger surface at 14 o C.

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 2.22P: A cylindrical liquid oxygen (LOX) tank has a diameter of 1.22 m, a length of 6.1 m, and...

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