Consider a machine surface that is made of a 5-mm thick alu- minum with a thermal conductivity of 237 W/m-K. During operation the machine dissipates about 300 W/m² of heat to the surroundings, and the inner aluminum surface is at 150°C. To prevent machine operators from thermal burns, the machine surface can be covered with insulation. The aluminum/ insulation interface has a thermal contact conductance of 3000 W/m²-K. What is the thickness required for the insulation layer with a thermal conductivity of 0.06 W/m-K in order to maintain the surface temperature at 45°C or lower? Insulation Aluminum machine surface k = 237 W/m-K 150°C

Consider a machine surface that is made of a 5-mm thick alu- minum with a thermal conductivity of 237 W/m-K. During operation the machine dissipates about 300 W/m² of heat to the surroundings, and the inner aluminum surface is at 150°C. To prevent machine operators from thermal burns, the machine surface can be covered with insulation. The aluminum/ insulation interface has a thermal contact conductance of 3000 W/m²-K. What is the thickness required for the insulation layer with a thermal conductivity of 0.06 W/m-K in order to maintain the surface temperature at 45°C or lower? Insulation Aluminum machine surface k = 237 W/m-K 150°C

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

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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

Consider a machine surface that is made of a 5-mm thick alu-
minum with a thermal conductivity of 237 W/m-K. During
operation the machine dissipates about 300 W/m² of heat to the
surroundings, and the inner aluminum surface is at 150°C. To
prevent machine operators from thermal burns, the machine
surface can be covered with insulation. The aluminum/
insulation interface has a thermal contact conductance of
3000 W/m²-K. What is the thickness required for the insulation
layer with a thermal conductivity of 0.06 W/m-K in order to
maintain the surface temperature at 45°C or lower?
Insulation
Aluminum machine surface
k= 237 W/m-K
150°C

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