An insulated steam pipe is covered with two layers of insulation as seen figure below. Draw the thermal resistance network. Develop a formula to calculate the heat transfer rate per unit length of the pipe. How can you determine the temperature difference AT across the pipe wall and second insulation layer. T = 250°C. Ins.2 Ins. 1 Pipe - T2 = 20°C

An insulated steam pipe is covered with two layers of insulation as seen figure below. Draw the thermal resistance network. Develop a formula to calculate the heat transfer rate per unit length of the pipe. How can you determine the temperature difference AT across the pipe wall and second insulation layer. T = 250°C. Ins.2 Ins. 1 Pipe - T2 = 20°C

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.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.37P: 1.37 Mild steel nails were driven through a solid wood wall consisting of two layers, each 2.5-cm...

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Estimate the rate of heat loss per unit length from a 5-cm ID, 6-cm OD steel pipe covered with high-temperature insulation having a thermal conductivity of 0.11 W/(m K) and a thickness of 1.2 cm. Steam flows in the pipe. It has a quality of 99% and is at 150C. The unit thermal resistance at the inner wall is 0.0026(m2K)/W the heat transfer coefficient at the outer surface is 17W/(m2K) and the ambient temperature is 16C.
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1.37 Mild steel nails were driven through a solid wood wall consisting of two layers, each 2.5-cm thick, for reinforcement. If the total cross-sectional area of the nails is 0.5% of the wall area, determine the unit thermal conductance of the composite wall and the percent of the total heat flow that passes through the nails when the temperature difference across the wall is 25°C. Neglect contact resistance between the wood layers.
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