A steel pipe 150mm external diameter conveys steam at a temperature of 260°C and is covered by two layers of lagging, each 50mm thick. The thermal conductivity coefficient of the inside layer of lagging is 0.0865W/mK while that of the outside layer is 0.0952W/mK. The outside surface temperature of the steel pipe can be taken as being the same temperature of the steam. The ambient temperature is 27°C and the heat transfer coefficient of the outside surface is 15W/m²K. Calculate: 3.1 the heat lost/hr for a pipe length of 30m;

A steel pipe 150mm external diameter conveys steam at a temperature of 260°C and is covered by two layers of lagging, each 50mm thick. The thermal conductivity coefficient of the inside layer of lagging is 0.0865W/mK while that of the outside layer is 0.0952W/mK. The outside surface temperature of the steel pipe can be taken as being the same temperature of the steam. The ambient temperature is 27°C and the heat transfer coefficient of the outside surface is 15W/m²K. Calculate: 3.1 the heat lost/hr for a pipe length of 30m;

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 7.37P

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