A hot-water pipe (k = 50 W/m K) for house heating in winter season, made of 3/4-inch schedule 40 pipe (OD = 25.5 mm; thickness = 2.0 mm) is 10 meters long and contains water at 60 C. The air around the pipe is at 20C. The heat transfer coefficient inside and outside the pipe are 1,120 W/m2 K and 15 W/m2 K, respectively. Insulation with thermal conductivity of 20 W/m K is to be added to the pipe. Determine the heat loss from the pipe due to insulation of 120 mm thick.

A hot-water pipe (k = 50 W/m K) for house heating in winter season, made of 3/4-inch schedule 40 pipe (OD = 25.5 mm; thickness = 2.0 mm) is 10 meters long and contains water at 60 C. The air around the pipe is at 20C. The heat transfer coefficient inside and outside the pipe are 1,120 W/m2 K and 15 W/m2 K, respectively. Insulation with thermal conductivity of 20 W/m K is to be added to the pipe. Determine the heat loss from the pipe due to insulation of 120 mm thick.

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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