A 2-in steel pipe has an inside diameter of 5.25cm and an outside diameter of 6.03cm. The pipe has a thermal conductivity of k= 36 W/m*K that is insulated with a 2-cm-thick-layer of insulation (k=0.02 W/m*K). The inside surface of the pipe is maintained at a temperature of 60°C, and the outside surface of the insulation is maintained at a temperature at 20°C. Find the heat transfer from the pipe per meter of length.

A 2-in steel pipe has an inside diameter of 5.25cm and an outside diameter of 6.03cm. The pipe has a thermal conductivity of k= 36 W/mK that is insulated with a 2-cm-thick-layer of insulation (k=0.02 W/mK). The inside surface of the pipe is maintained at a temperature of 60°C, and the outside surface of the insulation is maintained at a temperature at 20°C. Find the heat transfer from the pipe per meter of length.

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.

Chapter3: Transient Heat Conduction

Section: Chapter Questions

Problem 3.16P: 3.16 A large, 2.54-cm.-thick copper plate is placed between two air streams. The heat transfer...

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3.16 A large, 2.54-cm.-thick copper plate is placed between two air streams. The heat transfer coefficient on one side is and on the other side is . If the temperature of both streams is suddenly changed from 38°C to 93°C, determine how long it takes for the copper plate to reach a temperature of 82°C.
2.9 In a large chemical factory, hot gases at 2273 K are cooled by a liquid at 373 K with gas-side and liquid-side convection heat transfer coefficients of 50 and , respectively. The wall that separates the gas and liquid streams is composed of a 2-cm thick oxide layer on the gas side and a 4-cm thick slab of stainless steel on the liquid side. There is a contact resistance between the oxide layer and the steel of . Determine the rate of heat loss from hot gases through the composite wall to the liquid.
1.19 A cryogenic fluid is stored in a 0.3-m-diameter spherical container is still air. If the convection heat transfer coefficient between the outer surface of the container and the air is 6.8 , the temperature of the air is 27°C, and the temperature of the surface of the sphere is –183°C, determine the rate of heat transfer by convection.
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2.55 A long, 1-cm-diameter electric copper cable is embedded in the center of a 25-cm-square concrete block. If the outside temperature of the concrete is 25oC and the rate of electrical energy dissipation in the cable is 150 W per meter length, determine temperatures at the outer surface and at the center of the cable.
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