A steel tube with a thermal conductivity of 45 W/m.K carries a fluid at 200°C, with a convection heat transfer coefficient of 210 W/m2./K. The tube has an external diameter of 5 cm, a wall thickness of 1 cm and a length of 2 m. The ambient air and surroundings are at 25°C, with a convection heat transfer coefficient of 25 W/m2.K. Neglecting the effects of radiation, determine: 1) resistance by conduction through the pipe wall 2) the convection resistance inside the tube 3) The total heat transfer rate

A steel tube with a thermal conductivity of 45 W/m.K carries a fluid at 200°C, with a convection heat transfer coefficient of 210 W/m2./K. The tube has an external diameter of 5 cm, a wall thickness of 1 cm and a length of 2 m. The ambient air and surroundings are at 25°C, with a convection heat transfer coefficient of 25 W/m2.K. Neglecting the effects of radiation, determine: 1) resistance by conduction through the pipe wall 2) the convection resistance inside the tube 3) The total heat transfer rate

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.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.1P: A plane wall, 7.5 cm thick, generates heat internally at the rate of 105 W/m3. One side of the wall...

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A steel tube with a thermal conductivity of 45 W/m.K carries a fluid at 200°C, with a convection heat transfer coefficient of 210 W/m2./K. The tube has an external diameter of 5 cm, a wall thickness of 1 cm and a length of 2 m. The ambient air and surroundings are at 25°C, with a convection heat transfer coefficient of 25 W/m2.K. Neglecting the effects of radiation, determine: 1) resistance by conduction through the pipe wall 2) the convection resistance inside the tube 3) The total heat transfer rate 4) The temperature of the outer surface of the tube 5) The total resistance considering the effects of radiation only on the outside, with the coefficient hr = 2W/m2.K 6) The new heat transfer rate, considering the effects of radiation, if an additional layer of 15 mm thick foam with a conductivity of 0.03 W/m.K is added to the system. 7) The critical insulation radius of the system after adding this insulating layer.
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