Rev1.0 1 February26,2015

SteamCycleSimulationHYSYSv8.6TheattachedgivesstepstosetupasimulationinHYSYSv8.6tomodelasimpleRankinesteamcycleforelectricityproduction.Thesystemconsistingof:

Fuelgassidewithairblower,combustionchamber,&fuelgassideofthesteamboiler. Steamsidewithsteamturbine,steamcondenser,condensatepump,&steamsideofthe

boiler.Thesimulationwillfirstbesetupassumingisentropicstepsfortherotatingequipment.Itwillthenbemodifiedtoaccountformorerealisticefficiencies(boththermodynamicandmechanical).WhenthesimulationissetuptheoverallPFDshouldlooklikethefollowingfigure.

CreatenewsimulationfileStarttheprogramfromStart,AllPrograms,AspenTech,ProcessModelingV8.6,AspenHYSYS,AspenHYSYSV8.6.WhentheprogramopenschoosetheNewbutton.

Rev1.0 2 February26,2015

DefinetheComponents&thePropertyModelsSpecifycomponents,fluidpropertypackages,&crudeoilassays

Thefirststepistoaddtwosetsofpurechemicalspeciestorepresent:

Steamasmodeledbypurewater&usingpropertycorrelationsconsistentwiththeASMESteamTables.

Thenaturalgasfuel,air,&combustionexhaustaspurelightcomponentsmodeledbythePengRobinsonequationofstate(EOS).

Letsdothesteamfirst.WithComponentListshighlightedclickontheAddbutton.Fromthelistofpurecomponentspickwater.Werenowreadytopickthepropertymodel.

Rev1.0 3 February26,2015

Thenextstepistopickafluidpropertypackage.FromtheFluidPackagesscreenclicktheAddbutton.ChoosetheASMESteamoptionandmakesureitisassociatedwithComponentList1.

Nowletsaddcomponentstomodelthefuelsideofthesystem.GobacktotheComponentListsitem&clickontheAddbuttontocreateComponentList2.Weneedcomponentsforthefollowing:

Naturalgas.Fornowletsmodelthisasapossiblemixtureofmethane,ethane,&propane. Air.Fornowwellmodelthisasamixtureofoxygen&nitrogen. Combustiongases.Attheminimumwellalsoneedcarbondioxideandwater.However,

wellalsowanttotakeintoaccountincompletecombustion(formingcarbonmonoxide)aswellasNOxformation(fornowjustasNO,NO2,&N2O).

Fromthelistofpurecomponentspickthefollowingchemicalspecies.Thenextstepistoassociateadifferentfluidpropertypackageforthesecompounds(sincetheASMESteamTablesareonlyappropriateforpurewater).GobacktotheFluidPackagesscreen&clicktheAddbutton.ChoosethePengRobinsonoptionandmakesureitisassociatedwithComponentList2.

Rev1.0 4 February26,2015

Nowisagoodtimetosavethefilebeforewestartsettinguptheprocesssimulation.ClicktheFiletab&thentheSaveAsitem.

Rev1.0 5 February26,2015

Setup&SolvetheFlowsheetWorkingUnitsActivatetheSimulationoption.Notethatyoullseeablankflowsheet.WewouldliketoshowthecalculationswithamodifiedsetofSIunits,inparticular:

TemperatureasC. Pressureasbar(absolute). Massflowaskg/sec. Molarflowaskg.mol/sec. HeatdutyaskJ/sec. PoweraskW.

UndertheHometabclicktheUnitSetsbutton.UndertheAvailableUnitsSetsselectSI.YoucanexaminethelistunderDisplayUnitstodeterminewhatwillbeusedforthedisplayoftheresultsaswellasthedefaultunitsfortheinput.Mostoftheunitsarewhatwedesire,butnotall.Forexample,youcanseethatPressurewillbereportedinkPa,notquitewhatwewant.

Letscreateanewsetofunits&callitSIbarsec.WiththeSIunitshighlightedintheAvailableUnitsSetslistclicktheCopybutton.ChangetheUnitSetNametoSIbarsec.LetsnowexaminetheDisplayUnitsfortheonesofinterest(Temperature,Pressure,etc.)andmakesurethatareconsistentwithwhatwewant.TochangeweneedonlyclickonthedropdownlistintheUnitscolumn.Forexample,tochangePressurefromkPatobarweonlyneedtochoosetheappropriateoptionfromthelist.WhendoneclicktheOKbutton.

Rev1.0 6 February26,2015

SteamCycleWewillwanttocreateasimpleRankinecyclewiththefollowingprocessconditions:

Saturatedsteamproductionat125bar. Finalcondensationto20C. Steamturbineoperatingatidealreversibleconditions. Condensatepumpoperatingatidealreversibleconditions. Noextrapressuredropthroughheatexchangersorpiping.

LetsplacethefollowingunitsfromtheModelPalettetotheflowsheet1:Heater,Cooler,Expander,&Pump.Ultimatelyitwillbedepictedasfollows.

Letsdefinethecondensatepumpfirst.Doubleclickonthepumpicon(probablycalledP100).ChangethenametoCondensatePump.Specifynewstreamsfortheinlet,Condensate,theoutlet,HPWater,&theenergystream,WPump.MakesurethattheBasis1fluidpackageischosen.

1IftheModelPaletteisnotvisiblechoosetheViewtab&clickontheModelPalettebutton.

Rev1.0 7 February26,2015

Wewanttomakethisanidealreversiblepump.ClickontheParametersoption&changetheAdiabaticEfficiencyto100%.

Wecaninitializethewatercirculatingintheloopfromhere,too.ClickontheWorksheettab&choosetheCompositionoption.Enter1fortheH2OvalueundertheCondensatecolumn.Aninputformwillpopup&allowyoutoverifythatthisrepresentstheMolesFractionsbasis.ClicktheOKbutton.

ClickonConditionssowecanentervaluesfortheCondensateenteringthepump.SpecifytheTemperatureas20CandtheVapourfractionas0(i.e.,asaturatedliquid).Letsuseaflowbasisof1kg/s.NoticethatCondensatestreamisfullydefined&otherassociatedvaluesarecalculated(suchasthepressure,molarflow,heatflow,etc.)

Nowletsdefinethesteamsideoftheboiler.Doubleclickontheheatericon(probablycalledE100).ChangethenametoSteamBoiler.Pulldownthelistfortheinputstream&chooseHPWater.Specifynewstreamsfortheoutlet,HPSteam,&theenergystream,QBoiler.MakesurethattheBasis1fluidpackageischosen.

Rev1.0 8 February26,2015

Wewanttoassumeanegligiblepressuredropthroughthisexchanger.ClickontheParametersoption&changetheDeltaPto0.

Nowletsspecifytheconditionsforthehighpressuresteam.ClickontheWorksheettab&theConditionsoption.SpecifythePressureas125barandtheVapourfractionas1(i.e.,asaturatedvapor).NoticethatafterenteringthepressuretherestoftheconditionsfortheHPWaterstreamarecalculated(sincewenowknowtheoutletpressureofthepump,too).AfterenteringthevaporfractiontherestoftheconditionscanbecalculatedfortheoutletHPSteam&therequireddutyQBoiler.Nowletsdefinethesteamturbine.Doubleclickontheexpandericon(probablycalledK100).ChangethenametoSteamTurbine.Pulldownthelistfortheinputstream&chooseHPSteam.Specifynewstreamsfortheoutlet,TurbineExhaust,&theenergystream,WSteamTurbine.MakesurethattheBasis1fluidpackageischosen.

Rev1.0 9 February26,2015

Wewanttomakethisanidealreversibleexpander.ClickontheParametersoption&changetheAdiabaticEfficiencyto100%.

Donotapplyanyotherconditionsatthistime.Nowletsdefinethecondenser.Doubleclickonthecoolericon(probablycalledE101).ChangethenametoSteamCondenser.Pulldownthelistfortheinputstream&chooseTurbineExhaust.Pulldownthelistfortheoutletstream&chooseCondensate.Specifyanewenergystream,QCondenser.MakesurethattheBasis1fluidpackageischosen.

Wewanttoassumeanegligiblepressuredropthroughthisexchanger.ClickontheParametersoption&changetheDeltaPto0.

Nowallunits&streamsshouldbefullycalculated.Therearevariouswaystoviewtheresults.OnewayistoclickontheWorkbookitem.UndertheMaterialStreamstabwecanseetemperatures,pressures,&phaseconditions(i.e.,vaporfractions).UndertheEnergyStreamstabwecanseethecalculatedexchangerduties&rotatingequipmentpowers.

Rev1.0 10 February26,2015

Wecanalsoviewthisbasicinformationdirectlyontheflowsheet.Rightclickthevariousstreams&choosetheShowTableoption.Thiscanbedoneforallofthestreamsofinterest.(Thetableswillprobablyhavetobemovedaroundtomaketheresultsreadable.)Bydefaultthematerialstreamtablesshowthetemperature,pressure,&overallmolarflow.Toaddvaporfractiondoubleclickonthetable,clickAddVariable,chooseVapourFraction,clickOK,&closethePFDTableform.

Rev1.0 11 February26,2015

ThereisathirdoptionthatwouldallowyoutocalculatethethermalefficiencyofthesteamcycleaswellassummarizetheresultsaddaSpreadsheettothesimulation.FromtheModelPaletteaddaSpreadsheet;doubleclicktoopen.ChangethenametoSteamCycleSummary.ClickontheParameterstabandchangetheNumberofColumnstoatleast5andtheNumberofRowstoatleast11.ClickontheSpreadsheettab&setuptextfieldsthatlooklikethefigureontheright.

Rev1.0 12 February26,2015

WenowwanttoassociatemanyofthecelllocationstoresultscalculatedbyHYSYS.Forexample,rightclickoncellB2&chooseImportVariable;chooseCondensate,Temperature,&thenclickOK.Notethatthetemperatureof20.00Cappearsinthetable;alsonotethatitisformattedasboldblue,meaningthatthisisauserinputvalue.(Italsodenotesthatitcanbechangedfromhere,butmoreofthatlater.).Whenallvariablesareassociatedwiththeappropriatecellsthespreadsheetshouldlookasfollows.

Nowletsaddacouplecalculations.

ThenetpowerproducedwillbethatfromtheSteamTurbineminusthatneededbytheCondensatePump.IncellD10entertheformula=D8D9.

Wealsowouldtodirectlycalculatethethermalefficiencyofthesteamcycle,i.e.,theratioofthenetpowerproducedbytheheatinfromtheboiler.IncellD11entertheformula=100*D10/B8.

Rev1.0 13 February26,2015

Nowwehaveasummarytablethatwillshowinasingleplacematerialstreamresults,energystreamresults,unitoperationparameters,&calculatedresults.Forexample,wecanseethatthiscombinationofconditionswillresultinasteamcyclewitha41.25%thermalefficiency.

Notethatthisisalsoalivetable.Wecanchangeparametershere&theothervalueswillautomaticallyrecalculate.Forexample,ifweweretochangetheSteamTurbine&CondensatePumpadiabaticefficienciesto85%,thenallvalueswouldberecalculatedandwecouldseethatthethermalefficiencydropsto34.94%.

Fuel&CombustionSystemWewillwanttocreateasimplenaturalgasburner/boilerwiththefollowingprocessconditions:

Naturalgasisavailableatindustrialdeliverypressure,20barg&15C.Wewillcharacterizethenaturalgasas100%methane.

Airisavailableat25C.Wewillcharacterizetheairasa21/79O2/N2molarmixtureandbonedry(i.e.,nowater).Wewanttoaddenoughairsothatthereis20%excessoxygenbasedoncompletecombustionofthenaturalgas.

Thecombustionprocessoccursnearsatmosphericconditionssothenaturalgasmustbeletdowninpressure.However,ablowerisneededtopushtheairintothecombustionchamber.

Thepressuredropthroughtheburner/boiler/fluecombinationis0.3bar.

Rev1.0 14 February26,2015

Thefluegasisexhaustedtotheatmosphereat120C,atemperaturehighenoughtopreventanyliquiddropout&subsequentcorrosionproblems.

LetsplacethefollowingunitsfromtheModelPalettetotheflowsheet:Valve,Compressor,GibbsReactor2,&Cooler.Ultimatelyitwillbedepictedasfollows.(WelldiscusstheSpreadsheet,Set,&Adjustoperationsaswego.)

Letsdefinethenaturalgas&letdownvalvefirst.Doubleclickonthevalveicon(probablycalledVLV100).ChangethenametoGasLetDownValve.Specifynewstreamsfortheinlet,FuelGas,&theoutlet,LPFuel.MakesurethattheBasis2fluidpackageischosen.

2NotethatreactormodelsareundertheColumnstaboftheModelPalette.

Rev1.0 15 February26,2015

Wewillinitializethenaturalgasfromhere.ClickontheWorksheettab&choosetheCompositionoption.Enter1fortheMethanevalueundertheFuelGascolumn.Aninputformwillpopup&allowyoutoverifythatthisrepresentstheMolesFractionsbasis.ClicktheNormalizebuttontosettheothercompositionsaszero.ClicktheOKbutton.

ClickonConditionssowecanentervaluesfortheFuelGasenteringthepump.SpecifytheTemperatureas15CandthePressureas20barg(notethatthepressuregetsautomaticallyadjustedtoanabsolutebasis).Letsuseaflowbasisof1kg.mol/s.Letsspecifytheoutletpressureof0.3bargintheLPFuelcolumn(notethatthepressuregetsautomaticallyadjustedtoanabsolutebasis).NoticethatboththeFuelGas&LPFuelstreamsarefullydefined&otherassociatedvaluesarecalculated(suchasthemassflow,heatflow,etc.)

Rev1.0 16 February26,2015

Nowletsdefinetheair&theairblower.Doubleclickonthecompressoricon(probablycalledK100).ChangethenametoAirBlower.Specifynewstreamsfortheinputstream,Air,theoutlet,Air2,&theenergystream,WAirBlower.MakesurethattheBasis2fluidpackageischosen.

Wewanttomakethisanidealreversiblecompressor.ClickontheParametersoption&changetheAdiabaticEfficiencyto100%.

Rev1.0 17 February26,2015

Wewillinitializetheairstreamfromhere.ClickontheWorksheettab&choosetheCompositionoption.Enter0.21fortheOxygenvalueundertheAircolumn.Aninputformwillpopup&allowyoutoverifythatthisrepresentstheMolesFractionsbasis&finishenteringtherestofthevalues.Enter0.79fortheNitrogenvalue.ClicktheNormalizebuttontosettheothercompositionsaszero.ClicktheOKbutton.

ClickonConditionssowecanentervaluesfortheAirenteringthepump.SpecifytheTemperatureas25CandthePressureas0barg(notethatthepressuregetsautomaticallyadjustedtoanabsolutebasis).Asastartingpointletsdefinetheflowrateas12kg.mol/hr.Finally,letsspecifytheoutletpressureforAir2as0.3bargtomatchthatofthefuelgasaftertheletdownvalve.NoticethatboththeAir&Air2streamsarefullydefined&otherassociatedvaluesarecalculated(suchasthemassflow,heatflow,etc.)Nowitstimetomodelthecombustionportionofthefuelgasburner.Therearevariousoptionsfordoingthis.Oneofthesimplest(andwouldnormallybedoneforhandcalculations)wouldbetodefineallcombustionreactions&specifytheextentofconversionforeach.Instead,weregoingtotakeadvantageofthefullthermodynamiccapabilitiesofHYSYS&useareactorthatwillminimizetheGibbsfreeenergy.Allwehavetodoislisttheexpectedproducts&HYSYSwillcalculatetheresultingproductdistributionthathonorsthematerial&energybalancesaswellasanychemicalequilibriumlimitations.

Rev1.0 18 February26,2015

DoubleclickontheGibbsReactoricon(probablycalledGBR100).ChangethenametoCombustion.SelecttheexistingLPFuel&Air2streamsasinlets.Specifynewstreams,CombustionGas,asthevapouroutlet&CombustionLiquidsastheliquidoutlet.MakesurethattheBasis2fluidpackageischosen.

Thatsprettymuchit.Thedefaultsarezeropressuredrop&includeallspeciesinthecomponentlistaspotentialproduct.WecanexaminetheresultsbyclickingontheWorksheettab.SelectingConditionsshowsthatthereisonlyagasproducedatatemperatureof1731C.WecanthenlookattheresultingcompositionbyselectingComposition.Theresultsare,bydefault,shownasmolefractions.Notethatallofthemethanehasbeenconsumed.ThereisasmallamountofCOformed(asincompletecombustion)butsomeNOxhasalsobeencreatedfromtheN2intheair.

Nowletsseehowmuchheatcanbetransferredoutofthecombustiongases.

Rev1.0 19 February26,2015

Nowletsspecifythecombustiongassideoftheboiler.Doubleclickontheheatericon(probablycalledE100).ChangethenametoHRSG.Pulldownthelistfortheinputstream&chooseCombustionGas.Specifynewstreamsfortheoutlet,FlueGa,&theenergystream,QHRSG..MakesurethattheBasis2fluidpackageischosen.Wewillnotspecifyapressuredropacrosstheexchanger.Rather,wellspecifythepressureoutthestack.ClickontheWorksheettab&theConditionsoption.SpecifythePressureas0bargandtheTemperatureas120C.Nowtheconditionsfortheinlet&outletstreamscanbedeterminedaswellasthedutyavailable(asQHRSG).Therearestillacoupleitemstobedonetocleanupthesimulation.ThefirstisforamatterofconveniencehowshouldwespecifythepressureoftheAir2streamoutoftheblower?RightnowthepressureintotheCombustionoperationissetseparatelyforthetwoinletstreams(LPFuel&Air2).Ifastudywastobeperformed&thepressureweretochangethenhavingthespecificationsintwoseparatelocationscouldleadtothembeingchangeddifferently.Itsurewouldbenicetosetitonlyinonelocation&thenhavetheotherlocationupdateautomatically.WecandothiswithaSetoperation.FromtheModelPaletteplaceaSetoperationontheflowsheet.Doubleclickonit(probablycalledSET1).RenameasSetBlowerOutlet.DefinetheTargetVariableasthepressureoftheAir2stream.WellusetheSourceasthevaluefromLPFuel.OncethisisimplementedanychangesmadetothepressureofLPFuelwillbeautomaticallytransmittedtotheoutletpressureoftheairblower.

Rev1.0 20 February26,2015

Thesecondchangeinvolvesaconvenientwaytomakesurethatthecorrectamountofairisaddedtomatchtheexcessoxygenspec.Theamountofstoichiometricoxygenisdeterminedfromthecombustionreactions.Formethane,ethane,&propanethereactionsare,respectively: CH4+2O2CO2+2H2O C2H6+3.5O22CO2+3H2O C3H8+5O23CO2+4H2OThisshowsthatweneedtoknowthecompositionofthefuelgas(inmolaramounts)todeterminethestoichiometricamountofoxygenneeded.Theexcesspartisadditionaloxygen(asamultiplier)thatisadded.ThefinalconsiderationisthatthespecificationinHYSYSisnotjustfortherateofoxygenbutratheroftheair;sowehavetotakeintoaccountthecompositionoftheairaccountforthelargeamountofnitrogenalsobeintroducedintotheCombustionoperation.Sincewehavesetthecompositionofthefuelgastobepuremethane&thebasisflowrateto1kg.mol/secthenthestoichiometricoxygenflowrateistwicethis,2kg.mol/sec.Wealsoneedtoincreasethisby20%toincludethedesiredexcess.Andweneedtotakeintoaccounttheoxygencontentintheairtodeterminetheairrate.Sooverall: 2

2

Oair

O

1 2 1 0.2 11.43kg.mol/sec0.21excessstoich

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y

.WecoulddothesecalculationspriortorunningHYSYSandentertheairrate.OrwecoulddothecalculationswithinHYSYS.FromtheModelPaletteaddaSpreadsheet;doubleclicktoopen(probablycalledSPRDSHT1).ChangethenametoAirRateCalc.Usethedefaultnumberofrows&columns.ClickontheSpreadsheettab&setuptextfieldsthatlooklikethefigureontheright.

Rev1.0 21 February26,2015

WenowwanttoassociatemanyofthecelllocationstoresultscalculatedbyHYSYS.Forexample,rightclickoncellD3&chooseImportVariable;chooseAir,MastComponentMoleFrac,Oxygen,&thenclickOK.Letsassociateallofthedesiredmolarflowrates.Forexample,forthefuel,rightclickoncellB4&chooseImportVariable;chooseFuelGas,MolarFlow,&thenclickOK.AssociatethemolarflowfortheairtothecellD7.

Nowletsaddthefollowingcalculations:

cellD4,=(B2*2+B3*3.5+B4*5)*B5 cellD4,=D4*(1+D2) cellD4,=D5/D3 cellD4,=D7D6

Rev1.0 22 February26,2015

Nowwehaveatablethatwillcalculatethedesiredairflowrateforthespecifiedfuelgasflowrate.ThoughthespreadsheetcannotdirectlysettheairflowratewecandoitmanuallybydirectlychangingthevalueincellD7.

EventhoughthespreadsheetitselfcannotdirectlysettheflowrateoftheAirstreamitcanbeusedaspartofanAdjustoperation.FromtheModelPaletteplaceanAdjustoperationontheflowsheet.Doubleclickonit(probablycalledADJ1).RenameasAdjustAirRate.DefinetheAdjustedVariableasthemolarflowoftheAirstream.Wellusethecalculationforthedifferencebetweenthedesiredairrate&theactualastheTargetVariable;thisiscellD8intheAirRateCalcspreadsheet.SettheSpecifiedTargetValueas0.

Rev1.0 23 February26,2015

Tofinishwehavetosetvaluestocontrolthecalculations.ClickontheParameterstab.Increasethenumberofiterations(heresetfrom10to100).Settheminimumallowedvalueto0&themaximumallowedvaluetosomethingabovetheactualvalue(heresetto100).ThestatusareawillswitchtoOKwheniterationsaecompleted.

WecanopenuptheAirRateCalcspreadsheet&seethattheAirflowratehasbeenadjustedtomatchtheexcessoxygenspecification.

TyingtheTwoSystemsTogetherEventhoughthesteamcycle&fuelgassystemsareinthesameHYSYSflowsheettheyarereallymodeledseparately.Thesteamcyclehasconvergedwithabasisof1kg/secwatercirculationrate&thefuelsystemhasconvergedwithabasisof1kg.mol/secfuelgas.Wewilltiethesystemstogetherbypushingthedutyavailablefromthefuelsideoftheboilertothesteamside&adjustingthewatercirculationrateinthesteamcycle.

Rev1.0 24 February26,2015

Beforewemakeanydirectconnectionsletscreateaspreadsheettosummarizetheresultsfromthetwosystems.FromtheModelPaletteaddaSpreadsheet;doubleclicktoopen.ChangethenametoOverallPerformance.ClickontheSpreadsheettab&setuptextfieldsthatlooklikethefigureontheright.

Associatethematerialflows,temperature,&energyflowsasshowninthefigureontheright.

Nowletsconnectthetwosystems.

Rev1.0 25 February26,2015

DoubleclickontheCondensatestreaminthesteamcycleanddeletethevalueforthemassflowrate.Noticethattheintrinsicpropertiesforthestreamarestillcalculated(suchasthemolarenthalpy)buttheextrinsicpropertiesthatdependontheflowratearenowmissing.

DoubleclickontheiconfortheHRSGexchanger.GototheDesigntab&changetheEnergystreamfromQHRSGtoQBoiler.Thesimulationwillstillshowthatitiscomplete.YouwillwanttodeletetheunnecessarystreamQHRSGfromtheFlowsheet.

Sowhatschanged?Goback&lookattheCondensatestream.NoticethatHYSYShascalculatedawatercirculationratetomatchuptheamountofboilerheatneededinthesteamcycle(onakJ/kgbasis)withtheproperwaterflowrate(onakg/secbasis).

AdditionalStream&UnitAnalysesThereareadditionalanalysesthatwemaywanttoperformforthissimulation.Sincethegoaloftheprocessistocreatepowerweshouldbeveryinterestedtodeterminethevariousthermal

Rev1.0 26 February26,2015

efficienciesofthesystems.WehavealreadystartedthisanalysisbyputtingcalculationsintotheSteamCycleSummaryspreadsheettocalculatethesteamcyclesthermalefficiencybasedontheHYSYSresults.Tocalculatetheefficiencyoftheboilerweneedtodeterminetheheatingvalueofthefuelgasused.WehavealreadysetuptheformatoftheOverallPerformancespreadsheettodothesecalculations.OpentheOverallPerformancespreadsheetAssociatecellB3willtheHHVrightclickonthecell&chooseImportVariable;chooseFuelGas,HigherHeatingValue,thenclickOK.AssociatecellB4willtheLHVrightclickonthecell&chooseImportVariable;chooseFuelGas,LowerHeatingValue,thenclickOK.AddformulasintoD2&D3toputtheheatingonaflowingbasis(i.e.,multiplytheheatingvaluebythemolarflowrate).NotethateventhoughthenumbersappearunitlesstheyreallyhaveunitsofkJ/sec.Letsadd2columnsfortheefficiencyvalues.GototheParameterstab&changethenumberofcolumnsfrom4to6.Setuplabelsasshownontheright.

Nowwewanttoaddformulastocalculatethevariousvalues:

Rev1.0 27 February26,2015

cellF2,=D4/D2(alsochangeVariableTypetoUnitless) cellF3,=D4/D3(alsochangeVariableTypetoUnitless) cellF5,=(D8D7)/D4 cellF7,=(D8D7D6)/D2(alsochangeVariableTypetoUnitless) cellF8,=(D8D7D6)/D3(alsochangeVariableTypetoUnitless)

TherearemanyothercapabilitiesthatcanbeaddedsincetheSpreadsheetoperationcanmakechanges&calculationsinalivefashion.Forexample,anentirecontrolsheetcouldbesetuptomodifyvalues&directlycalculateresults.Cellscouldbesetupforthefollowinginputs:

Fuelgasflowrateanditspressure&temperature. Theairsatmosphericpressure&temperature. Airshumidity(wouldalsorequireadditionaloperationstoproperlyaddwaterwhile

keepingtherestofthecomponentsrelativeamountsthesame). Desiredexcessair. Pressuredropthroughtheboilersystem. Allowablestackoutlettemperature. Condensationtemperatureinthesteamcycle. Pressuredropthroughthesteamsideoftheboiler. Degreesofsuperheatintheboilersystem. Adiabatic&mechanicalefficienciesofallrotatingequipment.