A 3-layered composite wall is consists of different materials. Inside is wall 1: 300 mmthick, k = 1.5 W/m-K, then wall 2: 200 mm thick, k = 3.5 W/m-K, and wall 3: 100 mmthick. The inside surface is exposed to gases at 2192°F with surface film coefficient of5.3 BTU/hr-ft2-R. The temperature of air in the other side of the wall is 30°C with filmcoefficient of 10 W/m²-K. If the minimum temperature of wall 3 is 356°F, find theoverall heat transfer coefficient (W/m²-K) and the temperature drop (°C) at wall 2.

Given: K1=1.5w/m-k L1=300mm=0.3m K2=3.5w/mk L2=0.2m K3= thermal conductivity of third wall L3=0.1m…

A 3-layered composite wall is consists of different materials. Inside is wall 1: 300 mm thick, k = 1.5 W/m-K, then wall 2: 200 mm thick, k = 3.5 W/m-K, and wall 3: 100 mm thick. The inside surface is exposed to gases at 2192°F with surface film coefficient of 5.3 BTU/hr-ft²-R. The temperature of air in the other side of the wall is 30°C with film coefficient of 10 W/m²-K. If the minimum temperature of wall 3 is 356°F, find the overall heat transfer coefficient (W/m²-K) and the temperature drop (°C) at wall 2.

A 3-layered composite wall is consists of different materials. Inside is wall 1: 300 mm thick, k = 1.5 W/m-K, then wall 2: 200 mm thick, k = 3.5 W/m-K, and wall 3: 100 mm thick. The inside surface is exposed to gases at 2192°F with surface film coefficient of 5.3 BTU/hr-ft²-R. The temperature of air in the other side of the wall is 30°C with film coefficient of 10 W/m²-K. If the minimum temperature of wall 3 is 356°F, find the overall heat transfer coefficient (W/m²-K) and the temperature drop (°C) at wall 2.

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 2.62P

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