Oil in an engine is being cooled by air in a crossflow heat exchanger, where both fluids are unmixed. Oil (cph = 2047 J/kg·K) flowing with a flow rate of 0.026 kg/s enters the heat exchanger at 75°C, while air (cpc = 1007 J/kg·K) enters at 30°C with a flow rate of 0.21 kg/s. The overall heat transfer coefficient of the heat exchanger is 53 W/m2·K and the total surface area is 1 m2. Determine (a) the heat transfer effectiveness and (b) the outlet temperature of the oil.

Oil in an engine is being cooled by air in a crossflow heat exchanger, where both fluids are unmixed. Oil (cph = 2047 J/kg·K) flowing with a flow rate of 0.026 kg/s enters the heat exchanger at 75°C, while air (cpc = 1007 J/kg·K) enters at 30°C with a flow rate of 0.21 kg/s. The overall heat transfer coefficient of the heat exchanger is 53 W/m2·K and the total surface area is 1 m2. Determine (a) the heat transfer effectiveness and (b) the outlet temperature of the oil.

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 10.32P

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