Thermodynamics HW Solutions 982

# Thermodynamics HW Solutions 982 - Chapter 12 Radiation Heat...

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Chapter 12 Radiation Heat Transfer 12-99 A cylindrical furnace with specified top and bottom surface temperatures and specified heat transfer rate at the bottom surface is considered. The emissivity of the top surface and the net rates of heat transfer between the top and the bottom surfaces, and between the bottom and the side surfaces are to be determined. Assumptions 1 Steady operating conditions exist 2 The surfaces are opaque, diffuse, and gray. 3 Convection heat transfer is not considered. Properties The emissivity of the bottom surface is 0.90. T 1 = 700 K ε 1 = ? T 2 = 950 K ε 2 = 0.90 T 3 = 450 K ε 3 = 1 3 m Analysis We consider the top surface to be surface 1, the base surface to be surface 2, and the side surface to be surface 3. This system is a three- surface enclosure. The view factor from the base to the top surface of the cube is . The view factor from the base or the top to the side surfaces is determined by applying the summation rule to be F 12 02 = .
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## This note was uploaded on 01/24/2012 for the course PHY 4803 taught by Professor Dr.danielarenas during the Fall '10 term at UNF.

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