Heat Transfer Lesson The temperature will be increased from 10 (Degree Celsius oC) to 90 (Degree Celsius oC) while the water flows through a 1.5 cm inner diameter and 7 meter long straight pipe. Equipped with electric heater on the entire surface of the pipe. Even heating throughout. The outer surface of the heater is well insulated and therefore all heat generated in the heater in continuous operation is transferred to the water in the pipe. If the system provides a hot water flow rate of 6 liters / minute. (Thermophysical properties of water at 50 oC:ρ = 988 m3/kg, k= 0.6305 W/m oC, cp=4181 J/kg oC, Pr=3.628, μ= 0.0005471 kg/m.s ) a)Find the power of the resistance heater [W]. b)Calculate the inner surface temperature [oC] of the pipe at the outlet. c)Find the pressure drop [Pa]. d)Find the pump power [W] required to overcome this pressure drop.

Heat Transfer Lesson The temperature will be increased from 10 (Degree Celsius oC) to 90 (Degree Celsius oC) while the water flows through a 1.5 cm inner diameter and 7 meter long straight pipe. Equipped with electric heater on the entire surface of the pipe. Even heating throughout. The outer surface of the heater is well insulated and therefore all heat generated in the heater in continuous operation is transferred to the water in the pipe. If the system provides a hot water flow rate of 6 liters / minute. (Thermophysical properties of water at 50 oC:ρ = 988 m3/kg, k= 0.6305 W/m oC, cp=4181 J/kg oC, Pr=3.628, μ= 0.0005471 kg/m.s ) a)Find the power of the resistance heater [W]. b)Calculate the inner surface temperature [oC] of the pipe at the outlet. c)Find the pressure drop [Pa]. d)Find the pump power [W] required to overcome this 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.

Chapter11: Heat Transfer By Radiation

Section: Chapter Questions

Problem 11.62P

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