A wire of 6.5mm diameter at a temperature of 60 C is insulated by a plastic material having thermal conductivity (k) equal to 0.174 W/(m. C). The convection heat transfer coefficient h=8.722 W/(m. C). For the maximum heat loss to the ambient air at 20 C, what is the critical radius of insulation. Will the heat loss increase or decrease?

A wire of 6.5mm diameter at a temperature of 60 C is insulated by a plastic material having thermal conductivity (k) equal to 0.174 W/(m. C). The convection heat transfer coefficient h=8.722 W/(m. C). For the maximum heat loss to the ambient air at 20 C, what is the critical radius of insulation. Will the heat loss increase or decrease?

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.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.36P

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