A central heating system from a house consists of 50m of 15mm outside diameter copper pipe with a wall thickness of 1mm. This pipe is used to distribute water at a temperature of 70 degrees C. Calculate the rate of heat loss from the length of pipe if it is fitted with a 15mm radial thickness of insulation. Take the ambient air temperature to be 15 degrees C and the internal and external surface heat transfer coefficients to be 100 W/m².K and 8 W/m².K respectively. The thermal conductivity of the copper is known to be 400 W/m.K and 0.05 W/m.K for the insulation. State your answer correct to three significant figures in Watts. Assume steady state radial heat transfer.

A central heating system from a house consists of 50m of 15mm outside diameter copper pipe with a wall thickness of 1mm. This pipe is used to distribute water at a temperature of 70 degrees C. Calculate the rate of heat loss from the length of pipe if it is fitted with a 15mm radial thickness of insulation. Take the ambient air temperature to be 15 degrees C and the internal and external surface heat transfer coefficients to be 100 W/m².K and 8 W/m².K respectively. The thermal conductivity of the copper is known to be 400 W/m.K and 0.05 W/m.K for the insulation. State your answer correct to three significant figures in Watts. Assume steady state radial heat transfer.

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 2.38P: 2.38 The addition of aluminum fins has been suggested to increase the rate of heat dissipation from...

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