In a thermal system, water enters a 25-mm-diameter and 23-m-long circular tube with a mass flow rate of 0.1 kg/s at 25°C. The heat transfer from the tube surface to the water can be expressed in terms of heat flux as qs(x) = ax. The coefficient a is 400 W/m3, and the axial distance from the tube inlet is x measured in meters. Determine (a) an expression for the mean temperature Tm(x) of the water, (b) the outlet mean temperature of the water, and (c) the value of a uniform heat flux qs on the tube surface that would result in the same outlet mean temperature calculated in part (b). Evaluate water properties at 35°C.

In a thermal system, water enters a 25-mm-diameter and 23-m-long circular tube with a mass flow rate of 0.1 kg/s at 25°C. The heat transfer from the tube surface to the water can be expressed in terms of heat flux as qs(x) = ax. The coefficient a is 400 W/m3, and the axial distance from the tube inlet is x measured in meters. Determine (a) an expression for the mean temperature Tm(x) of the water, (b) the outlet mean temperature of the water, and (c) the value of a uniform heat flux qs on the tube surface that would result in the same outlet mean temperature calculated in part (b). Evaluate water properties at 35°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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