Hot water at 90°C flows on the inside of a 2.5-cm-ID steel tube with 0.8mm wall thickness at a velocity of 4 m/s. Engine oil at 20°C is forced across the tube at a velocity of 7 m/s. If the convection heat transfer coefficient at the inner and outer surface areas of the tube are 20,000 and 1167 W/m2-°C, respectively. Calculate the overall heat transfer coefficient based on the outer surface area of the tube. k (steel) = 36 W/m-°C

Hot water at 90°C flows on the inside of a 2.5-cm-ID steel tube with 0.8mm wall thickness at a velocity of 4 m/s. Engine oil at 20°C is forced across the tube at a velocity of 7 m/s. If the convection heat transfer coefficient at the inner and outer surface areas of the tube are 20,000 and 1167 W/m2-°C, respectively. Calculate the overall heat transfer coefficient based on the outer surface area of the tube. k (steel) = 36 W/m-°C

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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