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.

College Physics

10th Edition

ISBN:9781285737027

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter11: Energy In Thermal Processes

Section: Chapter Questions

Problem 40P: The thermal conductivities of human tissues vary greatly. Fat and skin have conductivities of about...

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