An electric wire, with 2 mm in diameter, is insulated by a rubberized liner (k = 0.13 W/m.K) of 2 mm thick. The coefficient of heat transfer by convection on the external surface of the lining is equal to 10 W/m?. K and the ambient air temperature equal to 20°C. If the temperature of the insulator cannot exceed 50°C, what is the maximum permissible electrical power that can be dissipated per unit length of the conductor?

An electric wire, with 2 mm in diameter, is insulated by a rubberized liner (k = 0.13 W/m.K) of 2 mm thick. The coefficient of heat transfer by convection on the external surface of the lining is equal to 10 W/m?. K and the ambient air temperature equal to 20°C. If the temperature of the insulator cannot exceed 50°C, what is the maximum permissible electrical power that can be dissipated per unit length of the conductor?

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 1.45P: An electronic device that internally generates 600 mW of heat has a maximum permissible operating...

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