Water at a temperature of 20 oC with a mass flow rate of 0.015 kg/s enters the pipe 2.5 cm in diameter with a uniform surface temperature of 90 oC. a) Determine the length of the thermal inlet region, Lt. b) If it is assumed that the flow is hydrodynamically and thermally formed, calculate the convection heat transfer coefficient and the length of the pipe required to heat the water to 70 oC. c) What is the rate of heat transfer to the water? d) Calculate the friction factor and pressure drop.

Water at a temperature of 20 oC with a mass flow rate of 0.015 kg/s enters the pipe 2.5 cm in diameter with a uniform surface temperature of 90 oC. a) Determine the length of the thermal inlet region, Lt. b) If it is assumed that the flow is hydrodynamically and thermally formed, calculate the convection heat transfer coefficient and the length of the pipe required to heat the water to 70 oC. c) What is the rate of heat transfer to the water? d) Calculate the friction factor and pressure drop.

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 7.3DP

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