Problem 05.089 - Heat exchangerHot exhaust gases of an internal combustion engine are to be used to produce saturated water vapor at 2 MPa pressure. The exhaustgases enter the heat exchanger at 400°C at a rate of 32 kg/min while water enters at 15°C. The heat exchanger is not well insulated,and it is estimated that 10 percent of heat given up by the exhaust gases is lost to the surroundings. If the mass flow rate of theexhaust gases is 15 times that of the water, determine the temperature of the exhaust gases at the heat exchanger exit and the rate ofheat transfer to the water. Use the constant specific heat properties of air for the exhaust gases. The constant pressure specific heat ofthe exhaust gases is taken to be cp 1.045 kJ/kg "C. The inlet and exit enthalpies of water are 62.98 kJ/kg and 2798.3 kJ/kg.=Exhaustgases400°CT2 MPasat. vap.HeatexchangerWater15°CThe temperature of the exhaust gases isThe rate of heat transfer iskW.°C.

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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 7.49P

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