Example 2.22: A steel pipe 25 mm internal diameter and 33 mm outer diameter and insulated with rockwool carries steam at 451 K (178°C). If the surrounding air temperature is 294 K (21°C), calculate the rate of heat loss from one metre length of pipe. The thickness of insulation is 38 mm. Thermal conductivities of steel and rockwool are 44.97 W/(mK) and 0.175 W/(m-K) respectively. The inside and outside heat transfer coefficients are 5678 W/(m²K) and 11.36 W/(m²K) respectively. Contact resistance between the pipe and insulation may be neglected.

Example 2.22: A steel pipe 25 mm internal diameter and 33 mm outer diameter and insulated with rockwool carries steam at 451 K (178°C). If the surrounding air temperature is 294 K (21°C), calculate the rate of heat loss from one metre length of pipe. The thickness of insulation is 38 mm. Thermal conductivities of steel and rockwool are 44.97 W/(mK) and 0.175 W/(m-K) respectively. The inside and outside heat transfer coefficients are 5678 W/(m²K) and 11.36 W/(m²K) respectively. Contact resistance between the pipe and insulation may be neglected.

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.

Chapter7: Forced Convection Inside Tubes And Ducts

Section: Chapter Questions

Problem 7.48P

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