Calculate the total thermal resistance between hot water and the surrounding ambient air for the insulated pipe as shown in the figure. Consider the length of the pipe to be 10 m. The air is flowing across at 0.6 m/s. Hot water has a mean velocity of 0.05 m/s and an average convection coefficient of 118 W/m².K. Assume the film temperature of the air to be same as the ambient temperature. Assume the bulk-mean temperature of water to be 50°C. Also assume that the outer surface (at D3) and the inner surface (at D₁) are isothermal. 0.11 K/W Water V Insulation k;= 0.5 W/m-K D₁ = 20 mm D₂ = 25 mm D₂ = 50 mm Pipe, k = 18 W/m.K Ambient air, 20°C

Calculate the total thermal resistance between hot water and the surrounding ambient air for the insulated pipe as shown in the figure. Consider the length of the pipe to be 10 m. The air is flowing across at 0.6 m/s. Hot water has a mean velocity of 0.05 m/s and an average convection coefficient of 118 W/m².K. Assume the film temperature of the air to be same as the ambient temperature. Assume the bulk-mean temperature of water to be 50°C. Also assume that the outer surface (at D3) and the inner surface (at D₁) are isothermal. 0.11 K/W Water V Insulation k;= 0.5 W/m-K D₁ = 20 mm D₂ = 25 mm D₂ = 50 mm Pipe, k = 18 W/m.K Ambient air, 20°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.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.7P: 5.7 The average Reynolds number for air passing in turbulent flow over a 2-m-long, flat plate is ....

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