1. A pipe of outside diameter 20 mm is to be insulated with asbestos whichhas a mean thermal conductivity of 0.1 W/m-deg. The local coefficient ofconvective heat to the surroundings is 5W/m?-deg. Comment upon the utilityof asbestos as the insulating material. What should be the minimum value ofthermal conductivity of insulating material to reduce heat transfer?ANSWER: 0.05 W/m-C

Given Outer diameter, do = 20 mm Outer radius, ro = 10 mm = 0.01 m Heat transfer coefficient, h…

1. A pipe of outside diameter 20 mm is to be insulated with asbestos which has a mean thermal conductivity of 0.1 W/m-deg. The local coefficient of convective heat to the surroundings is 5W/m2-deg. Comment upon the utility of asbestos as the insulating material. What should be the minimum value of thermal conductivity of insulating material to reduce heat transfer? ANSWER: 0.05 W/m-C

1. A pipe of outside diameter 20 mm is to be insulated with asbestos which has a mean thermal conductivity of 0.1 W/m-deg. The local coefficient of convective heat to the surroundings is 5W/m2-deg. Comment upon the utility of asbestos as the insulating material. What should be the minimum value of thermal conductivity of insulating material to reduce heat transfer? ANSWER: 0.05 W/m-C

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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