A furnace wall comprises three layers of thickness 250 mm, 100 mm, and 150 mm with thermal conductivities of 1.65, k and 9.2 W/m K respectively. The inside is exposed to gases at 1250 °C with convection of 25 W/m2K, and the inside surface is at 1100 °C, the outside surface air at 25 °C with convection of 12 W/m2K. Determine the overall heat transfer coefficient in W/m2-K to 2 d.p. ?

A furnace wall comprises three layers of thickness 250 mm, 100 mm, and 150 mm with thermal conductivities of 1.65, k and 9.2 W/m K respectively. The inside is exposed to gases at 1250 °C with convection of 25 W/m2K, and the inside surface is at 1100 °C, the outside surface air at 25 °C with convection of 12 W/m2K. Determine the overall heat transfer coefficient in W/m2-K to 2 d.p. ?

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.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.9P: Heat is transferred at a rate of 0.1 kW through glass wool insulation (density=100kg/m3) with a 5-cm...

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