Hot oil, which enter a cross-flow heat exchanger at 200 C and leave at 100 C, are used to heat water at a flow rate of 1.5 kg/s from 30 to 120 C. The overall heat transfer coefficient based on the water-side surface area is U = 220 W/m2 . K. Determine : a) the required water surface area Ac using the NTU method(let effectiveness €=0.65). b) Ac when we change the water outlet temperature to 130C c) discuss the effect of changing the water outlet temperature to Ac? d)draw the temperature profile along the heat exchanger

Hot oil, which enter a cross-flow heat exchanger at 200 C and leave at 100 C, are used to heat water at a flow rate of 1.5 kg/s from 30 to 120 C. The overall heat transfer coefficient based on the water-side surface area is U = 220 W/m2 . K. Determine : a) the required water surface area Ac using the NTU method(let effectiveness €=0.65). b) Ac when we change the water outlet temperature to 130C c) discuss the effect of changing the water outlet temperature to Ac? d)draw the temperature profile along the heat exchanger

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 10.46P

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