Consider a material that can be altered with exposure to an electric field such that it undergoes a structural transition from an insulator (state) to an electrical conductor (state) when the field is applied. The material in both its insulator and conductor states has a phonon contribution to its thermal conductivity of kph= 2 W/m·K. What is the thermal conductivity of the material with and without an applied electric field? ( electrical resistivity is pe = 1x10-6 m/S at T=27C with an applied electric field) note: k=kph+ke

Consider a material that can be altered with exposure to an electric field such that it undergoes a structural transition from an insulator (state) to an electrical conductor (state) when the field is applied. The material in both its insulator and conductor states has a phonon contribution to its thermal conductivity of kph= 2 W/m·K. What is the thermal conductivity of the material with and without an applied electric field? ( electrical resistivity is pe = 1x10-6 m/S at T=27C with an applied electric field) note: k=kph+ke

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 1.34P: A section of a composite wall with the dimensions shown below has uniform temperatures of 200C and...

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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

What is the thermal conductivity of the material with and without an applied electric field? ( electrical resistivity is p_e = 1x10-6 m/S at T=27C with an applied electric field)

note: k=k_ph+k_e

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