5- Air flows at 120 C in a thin-wall stainless-steel tube with h=65 W/m2.•C. The inside diameter of the tube is 2.5 cm and the wall thickness is 0.4 mm. k =18 W/m• steel. The tube is exposed to an environment with h=6.5 W/m2.•C and TO =15 C. Calculate the overall heat-transfer coefficient and the heat loss per meter of length. What thickness of an insulation having k =40 mW/m • loss by 90 percent?. Answ(q=220W) °C for the °C should be added to reduce the heat

5- Air flows at 120 C in a thin-wall stainless-steel tube with h=65 W/m2.•C. The inside diameter of the tube is 2.5 cm and the wall thickness is 0.4 mm. k =18 W/m• steel. The tube is exposed to an environment with h=6.5 W/m2.•C and TO =15 C. Calculate the overall heat-transfer coefficient and the heat loss per meter of length. What thickness of an insulation having k =40 mW/m • loss by 90 percent?. Answ(q=220W) °C for the °C should be added to reduce the heat

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 7.24P

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