A pipe passes through a room in which the surrounding air is at 22 ºC. The diameter of the pipe is 200 mm, the length of the pipe is 3metersand its surface temperature is 250ºC and the emissivity of the surface is 0.9 What is the surface emissive power (radiation heat loss)? If convection heat transfer coefficient from the surface to the air is 20 W/m2.K, what is the rate of heat loss from the surface of pipe by convection? Total heat loss from the surface of the pipe per unit length

A pipe passes through a room in which the surrounding air is at 22 ºC. The diameter of the pipe is 200 mm, the length of the pipe is 3metersand its surface temperature is 250ºC and the emissivity of the surface is 0.9 What is the surface emissive power (radiation heat loss)? If convection heat transfer coefficient from the surface to the air is 20 W/m2.K, what is the rate of heat loss from the surface of pipe by convection? Total heat loss from the surface of the pipe per unit 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.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.56P: A pipe carrying superheated steam in a basement at 10C has a surface temperature of 150C. Heat loss...

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Similar questions

A pipe carrying superheated steam in a basement at 10C has a surface temperature of 150C. Heat loss from the pipe occurs by radiation (=0.6) and natural convection (hc=25W/m2K). Determine the percentage of the total heat loss by these two mechanisms.
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A steam pipe 200 mm in diameter passes through a large basement room. The temperature of the pipe wall is 500C, while that of the ambient air in the room is 20C. Determine the heat transfer rate by convection and radiation per unit length of steam pipe if the emissivity of the pipe surface is 0.8 and the natural convection heat transfer coefficient has been determined to be 10 W/m2K.
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1.10 A heat flux meter at the outer (cold) wall of a concrete building indicates that the heat loss through a wall of 10-cm thickness is . If a thermocouple at the inner surface of the wall indicates a temperature of 22°C while another at the outer surface shows 6°C, calculate the thermal conductivity of the concrete and compare your result with the value in Appendix 2, Table 11.
1.76 Explain a fundamental characteristic that differentiates conduction from convection and radiation.
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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