You are pumping liquid nitrogen at a temperature of -196°C through a long, thin-walled pipe; ignore the resistance of the pipe material and assume that the outside temperature of the pipe is the same as the liquid nitrogen. The pipe has an outside diameter of 12.0 cm; and is buried in the ground (k = 0.52 W/(m-k), ground surface temperature = 18.0°C) at a depth of 3.2 meters (distance from the surface of the ground to the centerline of the pipe). To reduce the heat loss from the pipe, it is insulated with a 5.0 cm layer of cryogenic insulation, k = 0.0017 W/(m-k). Draw a sketch of this problem; draw the resistor diagram, and assuming steady-state conditions calculate the heat gain per meter length of the pipe.

You are pumping liquid nitrogen at a temperature of -196°C through a long, thin-walled pipe; ignore the resistance of the pipe material and assume that the outside temperature of the pipe is the same as the liquid nitrogen. The pipe has an outside diameter of 12.0 cm; and is buried in the ground (k = 0.52 W/(m-k), ground surface temperature = 18.0°C) at a depth of 3.2 meters (distance from the surface of the ground to the centerline of the pipe). To reduce the heat loss from the pipe, it is insulated with a 5.0 cm layer of cryogenic insulation, k = 0.0017 W/(m-k). Draw a sketch of this problem; draw the resistor diagram, and assuming steady-state conditions calculate the heat gain per meter length of the pipe.

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter28: Current And Resistance

Section: Chapter Questions

Problem 58PQ

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