A 0.21cm diameter electrical wire at 32oC is covered by 0.05cm thick plastic insulation (k = 0.13 W/mK). The wire is exposed to a medium at 10oC with a combined convection and radiation heat transfer coefficient of 14 w/m2K. a) Determine the heat transfer rate of the wire. b) Determine if the plastic insulation on the wire will increase or decrease heat transfer from the wire. c) Determine the heat transfer rate of the wire with an added thermal contact resistance of 0.000176 m2K/W at the interface of the wire and the insulation.

A 0.21cm diameter electrical wire at 32oC is covered by 0.05cm thick plastic insulation (k = 0.13 W/mK). The wire is exposed to a medium at 10oC with a combined convection and radiation heat transfer coefficient of 14 w/m2K. a) Determine the heat transfer rate of the wire. b) Determine if the plastic insulation on the wire will increase or decrease heat transfer from the wire. c) Determine the heat transfer rate of the wire with an added thermal contact resistance of 0.000176 m2K/W at the interface of the wire and the insulation.

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.

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A 0.21cm diameter electrical wire at 32^oC is covered by 0.05cm thick plastic insulation (k = 0.13 W/mK). The wire is exposed to a medium at 10^oC with a combined convection and radiation heat transfer coefficient of 14 w/m²K.

a) Determine the heat transfer rate of the wire.

b) Determine if the plastic insulation on the wire will increase or decrease heat transfer from the wire.

c) Determine the heat transfer rate of the wire with an added thermal contact resistance of 0.000176 m²K/W at the interface of the wire and the insulation.

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