Q5B) A steel pipe of 170 mm inner diameter and 190 mm outer diameter with thermal conductivity 55 W/m. K is covered with two layers of insulation. The thickness of first layer is 25 mm (k = 0.1 W/m. K) and second layer thickness is 40 mm (k = 0. 18 W/m. K). The temperature of steam and inner surface of steam pipe is 320 °C and outer surface of insulation is 80 °C. Ambient air temperature is 25 °C. The surface coefficient for inside and outside surfaces are 230 W/m².K and 6 W/m².K respectively. Determine the heat loss per meter length of steam pipe and layer of contact temperatures and also calculate overall heat transfer coefficient.

Q5B) A steel pipe of 170 mm inner diameter and 190 mm outer diameter with thermal conductivity 55 W/m. K is covered with two layers of insulation. The thickness of first layer is 25 mm (k = 0.1 W/m. K) and second layer thickness is 40 mm (k = 0. 18 W/m. K). The temperature of steam and inner surface of steam pipe is 320 °C and outer surface of insulation is 80 °C. Ambient air temperature is 25 °C. The surface coefficient for inside and outside surfaces are 230 W/m².K and 6 W/m².K respectively. Determine the heat loss per meter length of steam pipe and layer of contact temperatures and also calculate overall heat transfer coefficient.

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 1.10P: 1.10 A heat flux meter at the outer (cold) wall of a concrete building indicates that the heat loss...

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Concept explainers

Conduction and Convection

When energy travels from one object to another it is said to have undergone heat transfer. Heat transfer is nothing but the transfer of thermal energy or internal energy from one thing to another, like e.g., when a vessel with water, kept on top of a burner, heats up because of the flame underneath it.

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Q5B) A steel pipe of 170 mm inner diameter and 190 mm outer diameter with thermal
conductivity 55 W/m. K is covered with two layers of insulation. The thickness of first layer is
25 mm (k = 0.1 W/m. K) and second layer thickness is 40 mm (k = 0. 18 W/m. K). The
temperature of steam and inner surface of steam pipe is 320 °C and outer surface of insulation is
80 °C. Ambient air temperature is 25 °C. The surface coefficient for inside and outside surfaces
are 230 W/m².K and 6 W/m².K respectively. Determine the heat loss per meter length of
steam pipe and layer of contact temperatures and also calculate overall heat transfer coefficient.

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