(3) A thick steel slab is initially at a uniform temperature of 25°C. When the slab is exposed to hot flue gases, the surface temperature suddenly changes to 450°C. Make calculations for the temperature in a plane 250 mm from the slab surface 5 hours after the operation of change in surface temperature. Find also the heat flowing into 2 square meters of this plane and the total energy flowing through the surface during the 5 hour period. It may be presumed that for steel, thermal conductivity k = 160 kJ/m hr deg, density p= 8000 kg/m3 and the specific heat capacity Cp = 0.48 kJ/kg deg.

(3) A thick steel slab is initially at a uniform temperature of 25°C. When the slab is exposed to hot flue gases, the surface temperature suddenly changes to 450°C. Make calculations for the temperature in a plane 250 mm from the slab surface 5 hours after the operation of change in surface temperature. Find also the heat flowing into 2 square meters of this plane and the total energy flowing through the surface during the 5 hour period. It may be presumed that for steel, thermal conductivity k = 160 kJ/m hr deg, density p= 8000 kg/m3 and the specific heat capacity Cp = 0.48 kJ/kg deg.

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.

Chapter6: Forced Convection Over Exterior Surfaces

Section: Chapter Questions

Problem 6.36P

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