Water at an average temperature of 110°C and an average velocity of 5.5 m/s flows through a 7-m-long stainless-steel tube (k = 14.2 W/m⋅K) in a boiler. The inner and outer diameters of the tube are Di = 1.0 cm and Do = 1.4 cm, respectively. If the convection heat transfer coefficient at the outer surface of the tube where boiling is taking place is ho = 7200 W/m2⋅°C, determine the overall heat transfer coefficient Ui of this boiler based on the inner surface area of the tube. It is given that the properties of water at 110°C are (Table A-9) ν=μρ=0.268×10−6 m2/s , k = 0.682 W/m⋅°C, and Pr = 1.58. The overall heat transfer coefficient of this boiler is _____ W/m2⋅°C.

Water at an average temperature of 110°C and an average velocity of 5.5 m/s flows through a 7-m-long stainless-steel tube (k = 14.2 W/m⋅K) in a boiler. The inner and outer diameters of the tube are Di = 1.0 cm and Do = 1.4 cm, respectively. If the convection heat transfer coefficient at the outer surface of the tube where boiling is taking place is ho = 7200 W/m2⋅°C, determine the overall heat transfer coefficient Ui of this boiler based on the inner surface area of the tube. It is given that the properties of water at 110°C are (Table A-9) ν=μρ=0.268×10−6 m2/s , k = 0.682 W/m⋅°C, and Pr = 1.58. The overall heat transfer coefficient of this boiler is _____ W/m2⋅°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 7.4P

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