AT T3 Solution - Applied Thermodynamics and Heat Transfer Tutorials 3rd Year 1st Semester PDF

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Applied Thermodynamics and Heat Transfer Tutorials 3rd Year 1st Semester...

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CURTINUNIVERSITY DepartmentofMechanicalEngineering AppliedThermodynamicsandHeatTransfer AppliedThermodynamicsTutorial3 1 Anadiabaticturbineofasteampowerplantreceivessteamat80barand500oCandproduces100MW ofpower.Theisentropicefficiency oftheturbineisestimatedtobe0.85.Theturbine dischargessteam toacondenserat0.07bar.Calculatemassflowrateofthesteamthroughtheturbine. Ifthecoolingwaterenters thecondenserat20 oCand leavesat35 oC,calculatethecoolingwaterflow raterequiredtocondensetheexhauststeamfromtheturbinetosaturatedwaterstateatthecondenser outlet.Determinetheoverallefficiencyoftheplantneglectingthefeedpumpwork. Ans:89.8kg/s,3037.7kg/s,0.344

2 AsteampowerplantoperateswithanidealregenerativeRankinecycleusinganopenfeedwaterheater. Theboilergeneratessuperheatedsteam at10 MPaand550 oC.Regenerativesteamforfeedheatingis extractedat1000kPa.Thecondenserpressureis10 kPa.Findthecycleefficiencyandcompareitwith thatofanidealRankinecyclewithoutregeneration. Ans.43.8%,41.0%

3 In a steam power plant operating on a regenerative Rankine cycle with reheat, the steam enters the turbineat8.5MPaand540oC,andexpandsisentropicallyto2.2MPa,wheresomesteamisextractedfor feedheatingwithanopenfeed heater whiletheremainder isreheatedto500 oCandsentbackto the turbineforfurtherexpansion.Thesteamexhaustsfromtheturbineat7 kPaand240 m/s.Thecooling waterentersthe condenserat20 oCandleavesat30 oC.Thepowerplantproduces60MWof power. Determinethesteamflowrateandthecoolingwaterflowrate. Ans.47.25kg/s,1784kg/s

4 A steam power plant operates on an enhanced Rankine cycle with an open feed water heater and reheating.Theplant’spressurereadingsare 17.0MPafortheboiler,2.00 MPa inthe feedheater, and 5.00kPainthecondenser.Theboiler/superheaterexittemperatureis550.0oC,anddrysaturatedvapour entersthecondenser.Thesteammassflowratethroughtheboileris180.0kg/s,whilethetotalfuelmass flowratefortheplantis12.43kg/s.Thefuelhasa calorificvalueof43.0MJ/kg,feedpumpwork and kineticand potentialenergychangesintheplantcycle arenegligible,andthe highpressureturbineis knowntohaveanisentropicefficiencyof82%. (a) DrawaT‐sdiagramtoillustratetheplantcycleindicatingallsteaminformationgivenabove.Include saturationtemperaturesasappropriate. (b) Calculatethesteamenthalpyandtemperatureattheexitofthehighpressureturbine. (c) Calculatethefractionoftheboilersteammassflowthatisbledoff tothefeedwater heater(i.e. calculate“y”forthefeedheater). (d) Calculate the mass flow rate of fuel burned in the boiler/superheater.  Hence, determine the temperatureattheoutletofthereheater. Ans.2016examsoln DrChrisFordafterProfessorTilakTChandratilleke...