8. A shell and tube heat exchanger (single shell, two tube pass) is used to cool oil from a large marine engine. Lake water (the shell-side fluid) enters the heat exchanger at 2 kg/s and 15 °C with a convection coefficient of 500 W/m2.K. Engine oil flows through 100 copper tubes (k = 399 W/m.K) at a rate of 1 kg/s (the flow rate per tube is therefore 0.01 kg/s). The oil enters the tubes at 140 °C, where each tube is 1.5 m long with inner and outer diameters of 6 and 8 mm, respectively. Assume the flow in the tubes is fully developed. (40 points) Engine oil: p = 854 kg/m³, c = 2118 J/kg. K, μ = 0.0356 N. s/m2, k = 0.318 W/m. K Lake water: Cp = 4180 J/kg. K (a) Find the overall heat transfer coefficient UA, in W/K. (b) Calculate the oil outlet temperature.

8. A shell and tube heat exchanger (single shell, two tube pass) is used to cool oil from a large marine engine. Lake water (the shell-side fluid) enters the heat exchanger at 2 kg/s and 15 °C with a convection coefficient of 500 W/m2.K. Engine oil flows through 100 copper tubes (k = 399 W/m.K) at a rate of 1 kg/s (the flow rate per tube is therefore 0.01 kg/s). The oil enters the tubes at 140 °C, where each tube is 1.5 m long with inner and outer diameters of 6 and 8 mm, respectively. Assume the flow in the tubes is fully developed. (40 points) Engine oil: p = 854 kg/m³, c = 2118 J/kg. K, μ = 0.0356 N. s/m2, k = 0.318 W/m. K Lake water: Cp = 4180 J/kg. K (a) Find the overall heat transfer coefficient UA, in W/K. (b) Calculate the oil outlet temperature.

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.

Chapter10: Heat Exchangers

Section: Chapter Questions

Problem 10.13P

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