Problem-3: Chilled water enters a thin-shelled 5-cm-diameter, 150-m-long pipe at 7°C at a rate of 0.98 kg/s and leaves at 8°C. The pipe is exposed to ambient air at 30°C with a heat transfer coefficient of 9 W/m²-K. If the pipe is to be insulated with glass wool insulation (k = 0.05 W/m.K) in order to decrease the temperature rise of water to 0.25°C, determine the required thickness of the insulation.

Problem-3: Chilled water enters a thin-shelled 5-cm-diameter, 150-m-long pipe at 7°C at a rate of 0.98 kg/s and leaves at 8°C. The pipe is exposed to ambient air at 30°C with a heat transfer coefficient of 9 W/m²-K. If the pipe is to be insulated with glass wool insulation (k = 0.05 W/m.K) in order to decrease the temperature rise of water to 0.25°C, determine the required thickness of the insulation.

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 7.16P

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