An economizer is to be purchased for a power plant. The unit is to be large enough to heat 7.5 kg/s of pressurized water from 71 to 182?C. There are 26 kg/s of flue gases (cp = 1000 J/(kg K)) available at 426?C. Estimate(a) The outlet temperature of the flue gases,(b) The heat transfer area required for a counterflow arrangement if the overall heat transfer coefficient is 57W/(m2 K).GIVENCounterflow heat exchanger - flue gases heating waterWater flow rate (mw) = 7.5 kg/sWater temperaturesTw,in = 71?CTw,out = 182?CGas flow rate (mg) = 26 kg/sGas specific heat (cpg) = 1000 J/(kg K)Gas inlet temperature (Tg,in) = 426?COverall heat transfer coefficient (U) = 57 W/(m2K)

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Gas Tain- 426°C m, - 26 kg/s Twoue- 182°C Twn -71°C Water my =7.5 kg/s