A steel tube 150mm inside diameter and 10mm thick, conveys wet steam at 17 bar and is surrounded by air at 27°C. The coefficient of heat transfer from the steam to the tube is 10kW/m2 K and the thermal conductivity for steel is 46.6 W/mK. Under these circumstances the energy loss due to heat transfer is 2000W per metre length of pipe. Show that, because the resistance to heat transfer is comparatively small between the steam and the pipe and within the pipe, the corresponding temperature drops are small compared with the temperature drop between the outside surface of the pipe and the air. If the pipe is covered with a 50mm thick layer of insulating material which has a thermal conductivity of 0.346 W/mK, determine the heat loss in watts per metre length of pipe, and the rate of condensation per 100m of pipeline under these conditions. Assume that the heat transfer coefficient from the surface of the insulating material to the air is 0.714 times that for the bare pipe. Answer: 609 W/m : 114kg/h steps on how to reach this

A steel tube 150mm inside diameter and 10mm thick, conveys wet steam at 17 bar and is surrounded by air at 27°C. The coefficient of heat transfer from the steam to the tube is 10kW/m2 K and the thermal conductivity for steel is 46.6 W/mK. Under these circumstances the energy loss due to heat transfer is 2000W per metre length of pipe. Show that, because the resistance to heat transfer is comparatively small between the steam and the pipe and within the pipe, the corresponding temperature drops are small compared with the temperature drop between the outside surface of the pipe and the air. If the pipe is covered with a 50mm thick layer of insulating material which has a thermal conductivity of 0.346 W/mK, determine the heat loss in watts per metre length of pipe, and the rate of condensation per 100m of pipeline under these conditions. Assume that the heat transfer coefficient from the surface of the insulating material to the air is 0.714 times that for the bare pipe. Answer: 609 W/m : 114kg/h steps on how to reach this

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.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.64P

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