Hot oil is to be cooled in a double-tube counter-flow heat exchanger. The copper inner tubes have a diameter of 2 cm and negligible thickness. The inner diameter of the outer tube (the shell) is 3 cm. Water flows through the tube at a rate of 0.5 kg/s. The Nusselt number for the forced convection between the oil and the external surface of the tube is Nuo = 5.45. If the length of the tube is 1m and ΔTlm = 45°C. Determine the rate of heat transfer. Water properties: ρ = 990 kg/m3, Pr = 3.91, k = 0.637 W/m °C, ν = 0.000000602 m2/s. Oil properties: k = 0.138 W/m °C

Hot oil is to be cooled in a double-tube counter-flow heat exchanger. The copper inner tubes have a diameter of 2 cm and negligible thickness. The inner diameter of the outer tube (the shell) is 3 cm. Water flows through the tube at a rate of 0.5 kg/s. The Nusselt number for the forced convection between the oil and the external surface of the tube is Nuo = 5.45. If the length of the tube is 1m and ΔTlm = 45°C. Determine the rate of heat transfer. Water properties: ρ = 990 kg/m3, Pr = 3.91, k = 0.637 W/m °C, ν = 0.000000602 m2/s. Oil properties: k = 0.138 W/m °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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