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/m K, and the inside surface is at 1100 °C. the outside surface air at 25 "C with convection of 12 W/m K. Determine the rate of heat transfer per unit area of the furnce wall considering the convective heat trafer coefficient in W/m2?

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/m K, and the inside surface is at 1100 °C. the outside surface air at 25 "C with convection of 12 W/m K. Determine the rate of heat transfer per unit area of the furnce wall considering the convective heat trafer coefficient in W/m2?

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 1.19P: 1.19 A cryogenic fluid is stored in a 0.3-m-diameter spherical container is still air. If the...

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Concept explainers

Conduction and Convection

When energy travels from one object to another it is said to have undergone heat transfer. Heat transfer is nothing but the transfer of thermal energy or internal energy from one thing to another, like e.g., when a vessel with water, kept on top of a burner, heats up because of the flame underneath it.

Question

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/mK, and the inside surface is at 1100 "C,
the outside surface air at 25 "C with convection of 12 W/m K. Determine the rate of
heat transfer per unit area of the furnce wall considering the convective heat trafer
coefficient in W/m27
Question 24 of 84 >
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