Consider a plane composite wall that is made of two materials of thermal conductivities ka = 205 W/m·K and kb = 46 W/m·K and thicknesses δa = 5 cm and δb = 2.5 cm. Material a adjoins a hot fluid at 150o for which ha = 12 W/m2 ·K and material b is in contact with a cold fluid at 30o for which hb = 23 W/m2 ·K. The wall is 2 m high and 2.5 m wide. Calculate the rate of heat transfer through the wall. Calculate the overall heat transfer coefficient if the interface between the two walls has a thermal contact resistance of 8.5 × 10-3 m2 ·K/W.

Consider a plane composite wall that is made of two materials of thermal conductivities ka = 205 W/m·K and kb = 46 W/m·K and thicknesses δa = 5 cm and δb = 2.5 cm. Material a adjoins a hot fluid at 150o for which ha = 12 W/m2 ·K and material b is in contact with a cold fluid at 30o for which hb = 23 W/m2 ·K. The wall is 2 m high and 2.5 m wide. Calculate the rate of heat transfer through the wall. Calculate the overall heat transfer coefficient if the interface between the two walls has a thermal contact resistance of 8.5 × 10-3 m2 ·K/W.

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.

Chapter4: Numerical Analysis Of Heat Conduction

Section: Chapter Questions

Problem 4.12P

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