It is proposed to cool oil in a counter-current, concentric tube heatexchanger composed of a thin-walled inner tube of 0.02 m diametercarrying oil and thin-walled, perfectly insulated outer tube of 0.05 mdiameter carrying water. The oil flow rate is 50.0 kg min-1 and it has to becooled from 90°C to 40°C using 60 kg min-1 water at 20°C.Determine the length required for the heat exchanger. Comment onthe practicality of this length. The physical properties of potatoesDensity, pSpecific heat capacity, cpThermal conductivity, k1080 kg m-3,3400 J kg-1 K1,Large: 0.4 W m-1 K-1, Small: 1.25 W m-1 K-1The physical properties of air at 20°CDensity, pSpecific heat capacity, cpViscosity, uThermal conductivity, kPrandtl number, Pr1.164 kg m-31007 J kg-1 K-11.84x10-5 Pa s0.03 W m-1 K-10.72The physical properties of waterDensity, pSpecific heat capacity, cpViscosity, µThermal conductivity, kPrandtl number, Pr1000 kg m3,4200 J kg-1 K-1,1.00x10-3 Pa s,0.64 W m-1 K-1,4.7The physical properties of oilDensity, pSpecific heat capacity, cpViscosity, uThermal conductivity, kPrandtl number, Pr880 kg m3,1900 J kg-1 K-1,5.00x10-3 Pa s,0.140 W m-1 K-1,68Heat transfer coefficient correlations1. Nu = 0.023RE0.8 Pr0.42. Nu = 0.53 (GrPr)025Re 2 10000gB(Ts-Too)d³1and g = 9.8 m s², ßT; = surface temperature, T, = bulk temperature, v =where Grthermal expansion coefficient,v2Tkinematic viscosity

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is proposed to cool oil in a counter-current, concentric tube heat exchanger composed of a thin-walled inner tube of 0.02 m diameter carrying oil and thin-walled, perfectly insulated outer tube of 0.05 m diameter carrying water. The oil flow rate is 50.0 kg min-1 and it has to be cooled from 90°C to 40°C using 60 kg min-1 water at 20°C. Determine the length required for the heat exchanger. Comment on the practicality of this length.

is proposed to cool oil in a counter-current, concentric tube heat exchanger composed of a thin-walled inner tube of 0.02 m diameter carrying oil and thin-walled, perfectly insulated outer tube of 0.05 m diameter carrying water. The oil flow rate is 50.0 kg min-1 and it has to be cooled from 90°C to 40°C using 60 kg min-1 water at 20°C. Determine the length required for the heat exchanger. Comment on the practicality of this length.

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 7.29P

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