2. A furnace wall is made up of three layer of thickness 150 mm, 110 mm, and 125 mm with thermal conductivity of 1.65 W/m-K, k2, and 9.2 W/m-K respectively. The inside is exposed to gases at 1050°C with a convection coefficient of 25 W/m²-K and the inside surface temperature is at 900°C, the outside air temperature is at 30°C with convection coefficient of 12 W/m²-K. Calculate: a. the unknown thermal conductivity: b. the outside surface temperature and mid-plane temperatures in °F.

2. A furnace wall is made up of three layer of thickness 150 mm, 110 mm, and 125 mm with thermal conductivity of 1.65 W/m-K, k2, and 9.2 W/m-K respectively. The inside is exposed to gases at 1050°C with a convection coefficient of 25 W/m²-K and the inside surface temperature is at 900°C, the outside air temperature is at 30°C with convection coefficient of 12 W/m²-K. Calculate: a. the unknown thermal conductivity: b. the outside surface temperature and mid-plane temperatures in °F.

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 8.8P

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