A two-layer 24 m² plane wall consists of a 250 mm thick inner concrete layer with thermal conductivity k, of 2 W/m K and a 80 mm thick outer insulation with k of 0.04 W/m K. The temperatures of wall inner and outer surfaces are t, = 28°C and tą = -9°C. Calculate (i) the rate of heat transfer and (ii) the temperature t, of the wall intermediate surface.

A two-layer 24 m² plane wall consists of a 250 mm thick inner concrete layer with thermal conductivity k, of 2 W/m K and a 80 mm thick outer insulation with k of 0.04 W/m K. The temperatures of wall inner and outer surfaces are t, = 28°C and tą = -9°C. Calculate (i) the rate of heat transfer and (ii) the temperature t, of the wall intermediate surface.

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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