A wall has an overall U value of 0.25 W/m^2K. It includes a layer of insulation 50 mm thick. The conductivity of the insulation is 0.035 W/mK. It is decided that the thickness of the insulation should be increased so that the U value is reduced to 0.20 W/m^2K. What is the new thickness of insulation required?

A wall has an overall U value of 0.25 W/m^2K. It includes a layer of insulation 50 mm thick. The conductivity of the insulation is 0.035 W/mK. It is decided that the thickness of the insulation should be increased so that the U value is reduced to 0.20 W/m^2K. What is the new thickness of insulation required?

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.

Chapter4: Numerical Analysis Of Heat Conduction

Section: Chapter Questions

Problem 4.12P

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