Two industrial steel pipes are carrying 200 °C steam. The internal diameter of both pipes are 2.0 cm and both are insulated with 2.5 cm thicker layer of polyurethane insulation on the outside. The wall thickness of the first pipe is 0.5 cm while the wall of the other pipe is 2.0cm thick. The temperature at the outside surface of the insulation is kept constant at 50 °C. Thermal conductivities of steel and polyurethane insulation are 50 W/mK and 0.15 w/mK respectively. Thicker pipe loss more heat True False

Two industrial steel pipes are carrying 200 °C steam. The internal diameter of both pipes are 2.0 cm and both are insulated with 2.5 cm thicker layer of polyurethane insulation on the outside. The wall thickness of the first pipe is 0.5 cm while the wall of the other pipe is 2.0cm thick. The temperature at the outside surface of the insulation is kept constant at 50 °C. Thermal conductivities of steel and polyurethane insulation are 50 W/mK and 0.15 w/mK respectively. Thicker pipe loss more heat True False

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.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.56P

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