Transient Heating of a Concrete Wall. A wall made of concrete 0.305 m thick isinsulated on the rear side. The wall at a uniform temperature of 10°C (283.2 K) isexposed on the front side to a gas at 843°C (1116.2 K). The convection coefficientis 28.4 W/m? · K, the thermal diffusivity is 1.74 x 10-3 m²/h, and the thermalconductivity is 0.935 W/m · K.(a) Calculate the time for the temperature at the insulated face to reach 232°C(505.2 K).(b) Calculate the temperature at a point 0.152 m below the surface at this sametime.Ans. (a) at/x; = 0.25, t = 13.4 h%3D

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Transient Heating of a Concrete Wall. A wall made of concrete 0.305 m thick is insulated on the rear side. The wall at a uniform temperature of 10°C (283.2 K) is exposed on the front side to a gas at 843°C (1116.2 K). The convection coefficient is 28.4 W/m2 · K, the thermal diffusivity is 1.74 x 10-3 m²/h, and the thermal conductivity is 0.935 W/m · K. (a) Calculate the time for the temperature at the insulated face to reach 232°C (505.2 K). (b) Calculate the temperature at a point 0.152 m below the surface at this same time.

Transient Heating of a Concrete Wall. A wall made of concrete 0.305 m thick is insulated on the rear side. The wall at a uniform temperature of 10°C (283.2 K) is exposed on the front side to a gas at 843°C (1116.2 K). The convection coefficient is 28.4 W/m2 · K, the thermal diffusivity is 1.74 x 10-3 m²/h, and the thermal conductivity is 0.935 W/m · K. (a) Calculate the time for the temperature at the insulated face to reach 232°C (505.2 K). (b) Calculate the temperature at a point 0.152 m below the surface at this same time.

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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