A steam pipe (k= 45 W/m-°C) having 70 mm inside diameter and 85 mm outside diameter is lagged with two insulation layers; the layer in contact with pipe is 35 mm asbestos (k = 0.15 W/m-°C) and is covered with 25 mm thick magnesia insulation (k = 0.075 W/m-°C). The heat transfer coefficients for the outside and inside surfaces are 220 W/m?.°C and 6.5 W/m?C respectively. Temperature of the steam is 350°C and the outside atmosphere is at 30°C. (a) Sketch the schematic diagram of the system in question showing all necessary details and given data. (b) Determine the steady loss of heat for 50 m length of pipe. (c) Find out the overall heat transfer coefficients based on inside and outside surfaces of the lagged steam pipe.

A steam pipe (k= 45 W/m-°C) having 70 mm inside diameter and 85 mm outside diameter is lagged with two insulation layers; the layer in contact with pipe is 35 mm asbestos (k = 0.15 W/m-°C) and is covered with 25 mm thick magnesia insulation (k = 0.075 W/m-°C). The heat transfer coefficients for the outside and inside surfaces are 220 W/m?.°C and 6.5 W/m?C respectively. Temperature of the steam is 350°C and the outside atmosphere is at 30°C. (a) Sketch the schematic diagram of the system in question showing all necessary details and given data. (b) Determine the steady loss of heat for 50 m length of pipe. (c) Find out the overall heat transfer coefficients based on inside and outside surfaces of the lagged steam pipe.

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 8.39P

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