Ql: A composite wall is made of 10 mm and 16 mm layers of materials of thermal conductivity 10 and 20 W/m K. The contact resistance between surfaces is 5 x 10 *m °C/W. The hot side is exposed to fluid at 400°C with h- 75 W/m2K and the cold side is exposed to fluids at 60°C with h- 400 W/m. K. Determine the heat flow, temperature drop of the first layer and overall heat transfer coefficient. Comment on the contribution of contact resistance.

Ql: A composite wall is made of 10 mm and 16 mm layers of materials of thermal conductivity 10 and 20 W/m K. The contact resistance between surfaces is 5 x 10 *m °C/W. The hot side is exposed to fluid at 400°C with h- 75 W/m2K and the cold side is exposed to fluids at 60°C with h- 400 W/m. K. Determine the heat flow, temperature drop of the first layer and overall heat transfer coefficient. Comment on the contribution of contact resistance.

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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