A 12 cm diameter steam pipe is covered by 2 layers of lagging. The inside layer is 3 cm thick and has a coefficient of thermal conductivity of 0.08 W/m-K. The outside layer is 4 cm thick and has a coefficient of thermal conductivity of 0.15 W/m-K. The steam main conveys steam a pressure of 1.7 MPa with 25 °C superheat. The outside temperature of the lagging is 27 °C. If the steam main is 35 m long, find the heat loss in kW.

A 12 cm diameter steam pipe is covered by 2 layers of lagging. The inside layer is 3 cm thick and has a coefficient of thermal conductivity of 0.08 W/m-K. The outside layer is 4 cm thick and has a coefficient of thermal conductivity of 0.15 W/m-K. The steam main conveys steam a pressure of 1.7 MPa with 25 °C superheat. The outside temperature of the lagging is 27 °C. If the steam main is 35 m long, find the heat loss in kW.

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.

Chapter9: Heat Transfer With Phase Change

Section: Chapter Questions

Problem 9.37P

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