A steel pipe 150mm external diameter conveys steam at a temperature of 260°c and it is covered by two layers of lagging each 50mm thick the thermal conductivity of the inside layer of the lagging is 0.086W/mk while that of the outside layer is 0.055W/mk the outside surface temperature of the steel pipe can be taken as being the same as the temperature of the steam while that of the outside layer of lagging is 27°c Determine a) the heat loss/h for a pipe length of 30m b) the interface temperature between the two layers of lagging

A steel pipe 150mm external diameter conveys steam at a temperature of 260°c and it is covered by two layers of lagging each 50mm thick the thermal conductivity of the inside layer of the lagging is 0.086W/mk while that of the outside layer is 0.055W/mk the outside surface temperature of the steel pipe can be taken as being the same as the temperature of the steam while that of the outside layer of lagging is 27°c Determine a) the heat loss/h for a pipe length of 30m b) the interface temperature between the two layers of lagging

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.

Chapter3: Transient Heat Conduction

Section: Chapter Questions

Problem 3.16P: 3.16 A large, 2.54-cm.-thick copper plate is placed between two air streams. The heat transfer...

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A steel pipe 150mm diameter conveys steam at a temperature of 260 degrees and is covered by two layers of lagging, each 50mm thick. The thermal conductivity coefficient of the inside layer of lagging is 0.086W/m.K while that of the outside layer is 0.055W/m.K. The outside surface temperature of the steel pipe can be taken as the same as the temperature of the system. The ambient temperature is 27 degrees. Calculate the heat lost per hour for pipe length 30m. Calculate the interface temperature between the two layers of lagging
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