Ethanol is vaporized at 788C (hfg 5 846 kJ/kg) in a double-pipe parallel-flow heat exchanger at a rate of 0.03 kg/s by hot oil (cp 5 2200 J/kg?K) that enters at 1208C. If the heat transfer surface area and the overall heat transfer coefficients are 6.2 m2 and 320 W/m2 ?K, respectively, determine the outlet temperature and the mass flow rate of oil using (a) the LMTD method and (b) the e2NTU method.

Ethanol is vaporized at 788C (hfg 5 846 kJ/kg) in a double-pipe parallel-flow heat exchanger at a rate of 0.03 kg/s by hot oil (cp 5 2200 J/kg?K) that enters at 1208C. If the heat transfer surface area and the overall heat transfer coefficients are 6.2 m2 and 320 W/m2 ?K, respectively, determine the outlet temperature and the mass flow rate of oil using (a) the LMTD method and (b) the e2NTU method.

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 7.46P

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