1.21 The thermal conductivity in a particular plane wall depends as follows on the wall temperature, T (°C): k = A + BT, where A and B are constants. The temperatures are T₁ and T2 on either side if the wall, and its thickness is L. By integration of Fourier's law, develop an expression for q. At what temperature should k be evaluated to avoid the need for integration?

1.21 The thermal conductivity in a particular plane wall depends as follows on the wall temperature, T (°C): k = A + BT, where A and B are constants. The temperatures are T₁ and T2 on either side if the wall, and its thickness is L. By integration of Fourier's law, develop an expression for q. At what temperature should k be evaluated to avoid the need for integration?

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Description: 1.21 The thermal conductivity in a particular plane wall depends asfollows on the wall temperature, T (°C): k = A + BT, where A and Bare constants. The temperatures are T₁ and T2 on either side if thewall, and its thickness is L. By integration of F

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 1.5P: To determine the thermal conductivity of a structural material, a large 15-cm-thick slab of the...

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