A steel tube with 5 cm internal diameter, 7.6 cm outer diameter and k=15W/m °C is covered with an isolative covering of thickness 2 cm and k= 0.2 W/m °C. A hot gas at 330 °C with h = 400 W/m².°C flows inside the tube. The outer surface of the insulation is exposed to cooler air at 30 °C with h = 60 W/m².°C. Calculate the heat loss from the tube to the air for 10 m of the tube and the temperature drop in the insulation layer.

A steel tube with 5 cm internal diameter, 7.6 cm outer diameter and k=15W/m °C is covered with an isolative covering of thickness 2 cm and k= 0.2 W/m °C. A hot gas at 330 °C with h = 400 W/m².°C flows inside the tube. The outer surface of the insulation is exposed to cooler air at 30 °C with h = 60 W/m².°C. Calculate the heat loss from the tube to the air for 10 m of the tube and the temperature drop in the insulation layer.

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter21: Heat And The First Law Of Thermodynamics

Section: Chapter Questions

Problem 61PQ

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