Hot water at 120°C flows in a stainless-steel pipe (k, 15 W/m K) whose inner diameter is 1.6 cm and thickness is 0.2 cm. The pipe is to be covered with adequate insulation so that the temperature of the outer surface of the insulation does not exceed 40°C when the ambient temperature is 25°C. Taking the heat transfer coefficient for convection inside of the pipe and outside of insulation to be 70 and 20 W/m² •C respectively, determine the thickness (in cm) of fiberglass insulation (k, 0.038 W/m K) that needs to be installed on the pipe.

Hot water at 120°C flows in a stainless-steel pipe (k, 15 W/m K) whose inner diameter is 1.6 cm and thickness is 0.2 cm. The pipe is to be covered with adequate insulation so that the temperature of the outer surface of the insulation does not exceed 40°C when the ambient temperature is 25°C. Taking the heat transfer coefficient for convection inside of the pipe and outside of insulation to be 70 and 20 W/m² •C respectively, determine the thickness (in cm) of fiberglass insulation (k, 0.038 W/m K) that needs to be installed on the pipe.

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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