Steam at Ti = 380°C flows in a cast iron pipe (k = 75 W/m.°C) whose inner and outer diameters are Di = 6 cm and D2= 7.5 cm, respectively. The pipe is covered with 4 cm thick glass wool insulation with k = 0.05 W/m. °C. Heat is lost to the surroundings at T2= 8°C by natural convection and radiation, with a combined heat transfer coefficient of h) = 20 W/m? .°C. Taking the heat transfer coefficient inside the pipe to be hi = 70 W/m?.°C, determine the rate of heat loss from the steam per unit length of the pipe. Also determine the temperature drops across the pipe shell and the insulation.

Steam at Ti = 380°C flows in a cast iron pipe (k = 75 W/m.°C) whose inner and outer diameters are Di = 6 cm and D2= 7.5 cm, respectively. The pipe is covered with 4 cm thick glass wool insulation with k = 0.05 W/m. °C. Heat is lost to the surroundings at T2= 8°C by natural convection and radiation, with a combined heat transfer coefficient of h) = 20 W/m? .°C. Taking the heat transfer coefficient inside the pipe to be hi = 70 W/m?.°C, determine the rate of heat loss from the steam per unit length of the pipe. Also determine the temperature drops across the pipe shell and the insulation.

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter1: Temperature And Heat

Section: Chapter Questions

Problem 100P: One easy way to reduce heating (and cooling) costs is to add extra insulation in the attic of a...

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