An electric cable of 20 mm diameter is insulated with rubber, which is exposed to the atmosphere at 300 C. Calculate the most economical thickness of rubber insulation (k = 0.175 W/m.K). When cable surface temperature with and without insulation is at 700 C. Also calculate the percentage increase in heat dissipation and current carrying capacity when the most economical thickness is provided. Take the heat transfer W coefficient, h =9.3 m²K

An electric cable of 20 mm diameter is insulated with rubber, which is exposed to the atmosphere at 300 C. Calculate the most economical thickness of rubber insulation (k = 0.175 W/m.K). When cable surface temperature with and without insulation is at 700 C. Also calculate the percentage increase in heat dissipation and current carrying capacity when the most economical thickness is provided. Take the heat transfer W coefficient, h =9.3 m²K

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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