Air flows at 120 °C in a thin-walled tube (k = 18 W/m °C) with h = 65 w/m²- °C. The inside diameter of the tube is 2.5 cm tand the thickness is 0.4 mm. The tube is exposed to an environment with h = 6.5 W/m²-C and temperature of 15 °C. Calculate the the heat loss for 1 m length. What thickness of insulation having k = 40 W/m-°C should be added to reduce heat loss by 90 %.

Air flows at 120 °C in a thin-walled tube (k = 18 W/m °C) with h = 65 w/m²- °C. The inside diameter of the tube is 2.5 cm tand the thickness is 0.4 mm. The tube is exposed to an environment with h = 6.5 W/m²-C and temperature of 15 °C. Calculate the the heat loss for 1 m length. What thickness of insulation having k = 40 W/m-°C should be added to reduce heat loss by 90 %.

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 7.20P

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