You are designing an industrial furnace to keep sheet metal at a fixed temperature. You decide a long, hemispherical furnace will be the best choice. The hemispherical portion is built from insulating brick to reflect the radiation from a ceramic plate onto the sheet metal, and the ceramic plate is heated by gas burners from below. The radius of the hemisphere is 1 m and the rest of the system properties can be found in the table below. You may neglect convection during your analysis. Temperature Emissivity Ceramic Plate 1600 K ε = 0.85 Sheet Metal 500 K ε = 1 Insulating Brick unknown ε = 0.6 a) Calculate the required heat input per unit length of the furnace (out of the page) that must be supplied by the gas burners. b) What is the temperature of the insulating brick surface?

You are designing an industrial furnace to keep sheet metal at a fixed temperature. You decide a long, hemispherical furnace will be the best choice. The hemispherical portion is built from insulating brick to reflect the radiation from a ceramic plate onto the sheet metal, and the ceramic plate is heated by gas burners from below. The radius of the hemisphere is 1 m and the rest of the system properties can be found in the table below. You may neglect convection during your analysis. Temperature Emissivity Ceramic Plate 1600 K ε = 0.85 Sheet Metal 500 K ε = 1 Insulating Brick unknown ε = 0.6 a) Calculate the required heat input per unit length of the furnace (out of the page) that must be supplied by the gas burners. b) What is the temperature of the insulating brick surface?

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.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.10P

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