40-m pipe has a nominal diameter of 40 mm and 5 mm thickness. Pipe is insulated with a 0.6 cm layer of asbestos, followed by a layer of cork 4 mm thick. Inside the pipe is steam having a temperature of 700°C with film coefficient of 6000 W/m²-K. If the ambient temperature of the air is 30°C and the film coefficient is 12 W/m²-K, calculate the minimum temperature of asbestos (°C). The thermal conductivity of steam pipe, asbestos and cork are 0.045 kW/m-K, 0.058 W/m-K and 0.043 W/m-K respectively.

40-m pipe has a nominal diameter of 40 mm and 5 mm thickness. Pipe is insulated with a 0.6 cm layer of asbestos, followed by a layer of cork 4 mm thick. Inside the pipe is steam having a temperature of 700°C with film coefficient of 6000 W/m²-K. If the ambient temperature of the air is 30°C and the film coefficient is 12 W/m²-K, calculate the minimum temperature of asbestos (°C). The thermal conductivity of steam pipe, asbestos and cork are 0.045 kW/m-K, 0.058 W/m-K and 0.043 W/m-K respectively.

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.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.22P

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