A plane wall of an oven with an insulation coating is attached to an insulated wall. The thermal conductivity and thickness of the insulation coating are 0.1 W/(m K) and 1 mm, respectively. The material of the plane wall is stainless steel 304. The density, thermal conductivity, and specific heat capacity of the stainless steel 304 are 7900 kg/m³, 74.9 W/(m K), and 477 J/(kg K). respectively. The wall thickness of the stainless steel 304 is 15 mm. The temperature of the plane wall with the insulated coating is initially maintained at 30 °C. Suddenly, hot gas with a temperature of 1000 °C enters the oven. The convection heat transfer coefficient at the insulation coating surface is 70 W/(m²K).

A plane wall of an oven with an insulation coating is attached to an insulated wall. The thermal conductivity and thickness of the insulation coating are 0.1 W/(m K) and 1 mm, respectively. The material of the plane wall is stainless steel 304. The density, thermal conductivity, and specific heat capacity of the stainless steel 304 are 7900 kg/m³, 74.9 W/(m K), and 477 J/(kg K). respectively. The wall thickness of the stainless steel 304 is 15 mm. The temperature of the plane wall with the insulated coating is initially maintained at 30 °C. Suddenly, hot gas with a temperature of 1000 °C enters the oven. The convection heat transfer coefficient at the insulation coating surface is 70 W/(m²K).

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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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 plane wall of an oven with an insulation coating is attached to an insulated wall. The thermal
conductivity and thickness of the insulation coating are 0.1 W/(m K) and 1 mm, respectively.
The material of the plane wall is stainless steel 304. The density, thermal conductivity, and
specific heat capacity of the stainless steel 304 are 7900 kg/m³, 74.9 W/(mK), and 477 J/(kg K),
respectively. The wall thickness of the stainless steel 304 is 15 mm. The temperature of the
plane wall with the insulated coating is initially maintained at 30 °C. Suddenly, hot gas with a
temperature of 1000 °C enters the oven. The convection heat transfer coefficient at the
insulation coating surface is 70 W/(m²K).
Insulation Coating
Stainless Steel 304
Oven Gas
Perfectly Insulated Wall
3-1) What is the overall heat transfer coefficient per unit area from the gas to the surface of the
stainless steel? The answer should be given in the unit of W/(m²K).
3-2) What is the value of the Biot number?

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