Saturated steam at 3 atm will flow through a 3 in. Schedule 80 steel pipe. In order to decrease the heat losses to the surrounding air (at 20 oC) the pipe will be insulated. There are two types of insulating materials available, each with a thickness of 2.5 cm. Thermal conductivity of insulator A is 0.04 W/m.K and that of insulator B is 0.20 W/m.K. Both insulators will be used, in order to have the least heat loss. Which insulator should be covered outside? Assume that convective heat transfer coefficient between the insulated pipe and air is 15 W/m2K.

Saturated steam at 3 atm will flow through a 3 in. Schedule 80 steel pipe. In order to decrease the heat losses to the surrounding air (at 20 oC) the pipe will be insulated. There are two types of insulating materials available, each with a thickness of 2.5 cm. Thermal conductivity of insulator A is 0.04 W/m.K and that of insulator B is 0.20 W/m.K. Both insulators will be used, in order to have the least heat loss. Which insulator should be covered outside? Assume that convective heat transfer coefficient between the insulated pipe and air is 15 W/m2K.

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.

Chapter7: Forced Convection Inside Tubes And Ducts

Section: Chapter Questions

Problem 7.48P

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