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.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.23P

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