4- A furnace wall consists of three layers of blocks. The inner layer is of 10 cm thickness made of fire block (k = 1.04 W/m K). The intermediate layer of 25 cm thickness is made of normal block (k = 0.69 W/m K) followed by a 5 cm thick concrete wall (k = 1.31 W/m K). When the furnace is in continuous operation, the inner surface of the furnace is at 800°C while the outer concrete surface is at 50°C. Calculate (a) the rate of heat loss per unit area of the wall (b) the temperature at the interface of the fire block and normal block and (c) the temperature at the interface of the normal block and concrete wall. Take A-1m2. Anw(1515W, 654°C, 105°C)

4- A furnace wall consists of three layers of blocks. The inner layer is of 10 cm thickness made of fire block (k = 1.04 W/m K). The intermediate layer of 25 cm thickness is made of normal block (k = 0.69 W/m K) followed by a 5 cm thick concrete wall (k = 1.31 W/m K). When the furnace is in continuous operation, the inner surface of the furnace is at 800°C while the outer concrete surface is at 50°C. Calculate (a) the rate of heat loss per unit area of the wall (b) the temperature at the interface of the fire block and normal block and (c) the temperature at the interface of the normal block and concrete wall. Take A-1m2. Anw(1515W, 654°C, 105°C)

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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