Consider a furnace (as a plane wall) which has a thickness of 15 cm and a surface area of 1 m?. The inside surface of the furnace wall (the hot left side of the wall) is at temperature T1. The furnace wall is made of brick with thermal conductivity of 1.198 W/m.K. The outside surface of the furnace wall (the right side of the wall) has a surface emissivity of 0.8 and is maintained at T2=101 °C and subject to air at 25 °C with convection heat transfer coefficient of 20 W/m?.K. The surroundings temperature at the outside of the furnace wall is at 25 °C. Required: Draw a clear and consistent schematic of the problem and label the operating conditions on the schematic. Perform systematic analysis, state your assumptions and justify the equation used and determine the following (circle your final answers): (i) The rate of heat transfer by convection (in W); (ii) The rate of heat radiation (in W); (iii) The surface temperature of the furnace wall T1 (in °C); (iv) The rate of conduction heat transfer across the wall (in W).

Consider a furnace (as a plane wall) which has a thickness of 15 cm and a surface area of 1 m?. The inside surface of the furnace wall (the hot left side of the wall) is at temperature T1. The furnace wall is made of brick with thermal conductivity of 1.198 W/m.K. The outside surface of the furnace wall (the right side of the wall) has a surface emissivity of 0.8 and is maintained at T2=101 °C and subject to air at 25 °C with convection heat transfer coefficient of 20 W/m?.K. The surroundings temperature at the outside of the furnace wall is at 25 °C. Required: Draw a clear and consistent schematic of the problem and label the operating conditions on the schematic. Perform systematic analysis, state your assumptions and justify the equation used and determine the following (circle your final answers): (i) The rate of heat transfer by convection (in W); (ii) The rate of heat radiation (in W); (iii) The surface temperature of the furnace wall T1 (in °C); (iv) The rate of conduction heat transfer across the wall (in W).

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.

Chapter9: Heat Transfer With Phase Change

Section: Chapter Questions

Problem 9.37P

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