(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.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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