ML17207A646
| ML17207A646 | |
| Person / Time | |
|---|---|
| Site: | Saint Lucie  |
| Issue date: | 12/12/1979 |
| From: | UHRIG R E FLORIDA POWER & LIGHT CO. |
| To: | EISENHUT D G Office of Nuclear Reactor Regulation |
| References | |
| L-79-345, NUDOCS 7912140290 | |
| Download: ML17207A646 (57) | |
Text
ptREGULATORY FORMATION DISTRIBUTION SM(RIDS)ASCESSION NBR07912140290 DOCODATE~79/12/12NOTARIZED
~NOFACIL:50335St.LuciePlantiUnft1iFloridaPower8LightCo,AUTH~NAME'AUTHORAFFILIATION UMRIGgR~E~FloridaPower8LightCo,RECIP,NAME RECIPIENT AFFILIATION EISENHUTrD,G.
DivisionofOperating ReactorsDOCKET0'5000335 SU8JECT!Forwardsevaluation ofdesign8performance ofrefcoteconfiguration utilizing highetenrichment fue'I,Requests NRCapprovalby800114ofproposedemendto,revisemaxenrichment permitted byTechSpecs5,F1'ISTRIBUTION COBE:AOQISCOPIESRECEIVES:LTR
~ENCL'SIZE:~+TITLE:General*Distribution forafterIssuanceofOperating LicNOTES'ECIPIENT IDCODE/NAME ACTIONs05BCD/f8WQINTERNALREGF115COREPERFBR18REACSFTYBR20EEB22BRINKMANOELDEXTERNAL:
03LPDR23ACRSCOPIESL'TlRENCL7711221111110111616RECIPIENT IDCODE/NAME 02NRCPDR14TA/EDO17ENGRBR19PLANTSYSBR21KFLTTRTSYSEPBDOR04NSICCOPIESLTTRENCL>>1111111111111TOTALNUMBEROFCOPIESREQUIRED:
LTTR39ENCL38 tM)I0lq'I'I'I'JAMIM~fy>>ltil'$fiiMhf>>i'IMIfM,,gkk)<If.>>IMMM'Ie(lII1IIIII0M'>>f'iieI>>'I'IF1"'IPi'Mt>>a53fh(>,~f>>h,Igys>>q~1M~fhI'Ihh'hII)",I,If.0f5~Ij'h')f,I'Mif>'>>lM)~>>f'i>>i'I'0IllfIMIf'MfII14o>>'A4IllfIMiif1>>hf&~>>C>>*Ifi,W')"'MI,,Mtf,M>>0fMf>>fflMIf>>cIIf4>MI>>*~i~*>>>>c>>ccw>>>>>>>>wc>>l=:.cc>>fFcIa>>>>4>>e~=.cKw>>OE-CC'IIiIII>>IIg,lI>>MYIM OfficeofNuclearReactorRegulation Attention:
Mr.DarrellG.EisenhutActingDirectorDivisionof,Operating ReactorsU.S.NuclearRegulatory Commission Washington, D.C.20555
DearMr.Eisenhut:
P.O.BOX629100,MIAMI,FL331S2y<1lbgfi~~4xhFLORIDAPOWERSLIGHTCOMPANYDecember12,1979L-79-345Re:St.LucieUnit1DocketNo.50-335Reference Extended6cleSubmittal OnOctober4,1979(L-79-282),
FloridaPower&LightCompany(FPL)submitted aproposedlicenseamendment torevisethemaximumenrichment permitted byTechnical Specification 5.3.1topermitgreaterflexibility inassigning futurecoredesignfeaturesandassociated operating cyclelengthsforSt.LucieUnitl.Inordertocompletethereviewofthatproposedamend-ment,thestaffrequested thatFPLsubmitanevaluation ofthedesignandperformance ofareference core'configurationutilizing higherenrichment fuel.Inaccordance withthatrequest,FPLhere-withsubmitssuchanevaluation.
ThefourthfuelcycleforSt.LucieUnit1isthefirstcycleforwhichthehigherenrichment fuelcanbeutilized, consequently theattachedevaluation isbasedonahigherenrichment.
coreconfigur-ationwhichcouldbeutilizedforcycle4.Thehigherenrichment corecharacteristics havebeenexaminedwithrespecttothesafetyanalysesforSt.LucieUnit1,Cycle3and,inallcases,theCycle3safetyanalysesenvelopethenewconditions.
FPLmustreceiveNRCapprovalof'heproposedamendment byJanuary14,1980inordertoproceedwiththehigherenrichment coredesign.Adecisionaffecting manufacture ofthehighenrichment fuelforCycle4mustbemadeatthattime.Theattachment hasbeenreviewedandapprovedbytheFloridaPower&LightCompanyNuclearReviewBoardandtheSt.LucieFacilityReviewGroup.Vertryyours,RoberE.riVicePresident AdvancedSystems&Technology REU/MAS/rel Attachment cc:Mr.JamesP.O'Reilly, RegionIIHaroldF.Reis,Esquire)b')918140QQ(gPEOPLE...
SERVINGPEOPLE 0ST.LUCIEUNIT1REFERENCE EXTENDEDCYCLESUBMITTAL I.INTRODUCTION ANDSUMMARYThisrepor'tprovidesanevaluation ofthedesignandperformance fortheoperation ofSt.LucieIduringitsfourthfuelcycleatthefullratedpowerof2560t1WT.Operating conditions remainthesameasthosef'rCycle3.Thecorewillconsistof'resently tCoperating BatchC,D,andEassemblies togetherwithfreshBatchF=assemblies.
Systemrequirements havecreatedaneedforflexibility ibtheCycle3burnuplengthrangingfrom-7250 to8250tND/T.TheCycle4loadingpatterndescribed inthisreporthasbeendesignedtoaccommodate thisrangeofshutdownpoints.Inperforming analysesofpostulated accidents, determining limitingsafetysystemsettingsandestablishing limitingcondi'tions foroperations, valuesofkeyparameters werechosentoassurethatexpected.
conditions areenveloped withintheaboveCycle3burnuprange.ThesleevingofCEAguidetubescausedbywearoftheCEAfingersfollowsthesameprocedure asreportedforCycle3inReference 1.ForCycle4operation, onlysleevedassemblies willbeplacedunderCEAsandall88BatchFass'emblies willbesleeved.Theevaluations ofthereloadcorecharacteristics havebeenexamined.-withrespecttothesafetyanalysesdescribing Cycle3,(Reference 2)hereafter referredtoasthe"reference cycle".Inallcases,ithasbeenconcluded thatthereference cycle.safetyanalysesproperlyenvelope1thenewconditions.
Theresultofthisevaluation isthat'theoperation ofCycle4requiresonlyoneTechnical Specification changeentailing anincreaseinallowedenrichment from3.1w/oto3.7w/oU-235.
2.OPERATING HISTORYOFTHEREFERENCE CYCLESt.t,ucieUnitIispresently operating initsthirdfuelcycleutilizing BatchB,C,D,andEfuelassemblies atalicensedcorepowerlevelof2560t'lAT.Operation ofCycle3hascontinued atornear'icensedpower.Itispresently estimated thatCycle3willterminate duringMarch1980.Toallowforflexibility intheCycle3termination date,arangeofburnupsbetween7250and8250tQD/Thasbeenanticipated.
Operation ofCycle4isscheduled tocommenceintrayorJune1980.
3.GENERALDESCRIPTION TheCycle4corewillconsistofthenumbersandtypesofassemblies fromthevariousfuelbatchesasdescribed inTable3-1.TheprimarychangetothecoreforCycle4istheremovaloftheremaining 21BatchBassemblies and67ofthe68BatchCassemblies.
Theseassemblies willbereplacedby40BatchF(3.65w/oenrichment) and48BatchF>>(3.03w/oenri'chment)
"assemblies.
The48lowenrichment BatchF*assemblies containburnablepoisonpinswith12pinsperassembly.
Thelocationofpoisonpinswithinthelatticeisthesameasthatforpoisonpinassemblies presentinthereference cycle.Thefuelmanagement patterndeveloped forCycle4allowsforflexibility inCycle3burnuplengthbetween7250and8250HWD/T."TheloadingpatternisshowninFigure3-1.TheCycle4coreloadingpatternis90degreesrotationally symnetric.
Thatis,ifonequadrantofthecorewererotated90degreesintoitsneighboring
- quadrant, eachassemblywouldoverlayasimilarassembly.
Thissimilarity includesbatchtyne,numberoffuelrods,initialenrichment andbeginning ofcycleburnup.Figure3-2showsthebeginning ofCycle4assemblyburnupdistribution foraCycle3burnuplengthof7750t<WD/T.Theinitialenrichment ofeachassemblyisalsoshown.
Table'3-1St.LucieUnit1Ccle4CoreLoadinAssemblyDesignation NumberofAssemblies InitialEnrichment w/oU-235Beginning ofCycle4BatchAverageBurnupHHD/HTU(EOC3=7750HWD/T)InitialNumberShimofLoadingShimsw/0B4CTotalShimsTotalFuelRodsff*1402040.2840482.823.032.733.03'.733.653.0324,80015,70017,8006300930000000000123.030000005761767,0403,5207,0404,9287,0407,87221757637,616
~aj~gI
~eg~~~<<II<<IIIl<<IIIIIIIIII<<III~IIIII~II~olIIIII'llIIIIallIIeIII<<II'llIIIIIIIIII'llIIII<<II<<II'll0g8~~g) 4.0FUELDESIGN4.1Mechanical DesignThefuelassemblycomplement forCycle4isgiveninTable3-1.Themechanical designofthereloadfuelassemblies, BatchFisidentical toSt.Lucie-1BatchEfuel.C-Ehasperformed analytical predictions ofcladdingcreepcollapse, timeforallSt.Lucie-1fuelbatchesthatwillbeirradiated duringCycle4andhasconcluded thatthecollapseresistance of'llfuelrodsissufficient toprecludecollapseduringtheirdesignlifetime.
ThislifetimewillnotbeexceededbytheCycle4duration.
Theresultsofthisevaluation areshowninTable4-1.TheanalysesutilizedtheCEPANcomputercode(Reference 3)andincludedasinputconservative valuesofinternalpressure, claddingdimensions, claddingtemperature andneutronflux.4.2HardwareModifications toMitigateGuideTubeHear.IIBatchC,D,E,andFfuelassemblies tobeinstalled inCEAlocations inCycle4willhavestainless steelsleevesinstalled intheguidetubesinordertomitigateguidetubewear.Adetaileddiscussion ofthedesignofthesleevesanditseffectsonreactoroperation iscontained inReference
- 4.
4.3ThermalDesignUsingtheFATESmodel(Reference 5),thethermalperformance ofthevarioustypesoffuelassemblies hasbeenevaluated withrespecttotheir'Cycles1,2,and3burnups,proposedburnups'uring Cycle4,theirrespective fuelgeometries, andexpectedfluxlevelsduringCycle4.TheBatchEfuelh'asbeendetermi'ned tobethelimitingfuelbatchwithrespecttostoredenerqy.4.4ChemicalDesignThemetallurgical requirements ofthefuelcladdingandthefuelassemblystructural membersfortheBatchFfuelhavenotbeenchangedfromtheoriginalCycles1,2,and3designs.Therefore,
'hechemicalormetallurgical performance oftheBatchFfuel>>illbeunchanged fromthatoftheoriginalcorefuelanddiscussions intheFSAR,Reference 6arestillvalid.4.5Operating Experience Fuelassemblies incorporating thesamedesignfeaturesastheSt.LucieUnit1,BatchFfuelassemblies havehadoprating"experiences atCalvert.Cliffs1and2,FortCalhoun1,Hillstone II,Maine-Yankee andpreviousreloadcyclesforSt.Lucie-l.Theoperating experience hasbeensuccessful exceptfortheCEAguidetubewearprohlenwhichhasbeenaddressed inSection4.2.
'Tamil4-i~Predicted gadCol)apseTiw>Coivpa~ik toI'rebec".ed Operating Tir.~0 5.0NUCLEARDESIGN5.1PhysicsCharacteristics 5.1.1FuelManagement TheCycle4fuelmanagement employsamixedcentralregionasdescribed'n Section3,Figure3-1.ThefreshBatchFiscomprised oftwosetsofassemblies, eachhavingauniqueenrichment inordertominimizeradialpowerpeaking.Thereare40assemblies withanenrichment of3.65wt/U-235and48assemblies withanenrichment of3.03wt/U-235and12poisonshimsperassembly.
Withthisloading,theCycle4burnupcapacityforfullpowerloperation isexpectedtobebetween14,300MWD/Tand14,900MWD/T,depending onthefinalCycle3termination point.TheCycle4corecharacteristics havebeenexaminedforCycle3terminations between7250and8250MWD/Tandlimitingvaluesestablished forthesafetyanalyses.'he loadingpattern(seeSection3)isapplicable toanyCycle3termina-tionpointbetweenthestatedextremes.
Physicscharacteristics including reactivity coefficients forCycle4arelistedinTable5-1alongwiththecorresponding valuesfromthereference cycle.Pleasenotethatthevaluesofparameters actuallyemployedinsafetyanalysesaredifferent thanthosedisplayed inTable5-1andaretypically chosentoconservatively bound.predicted valueswithaccommodation forappropriate uncertainties andallowances.
Table5-2presentsasummaryofCEAshutdownworthsandreactivity allowances forCycle4withacomparison toreference cycledata.Table5-2generally characterizes thechangesinreactivity thatoccurduringatripfromfullpowerwithacorresponding changeincoreparameters tothezeropowerstate.Itisnotinte'nded torepresent anyparticular limitingA00oraccident, althoughthequantityshownas"Shutdown Margin"represents thenumerical valueoftheworthwhichisappliedtothehotzeropowersteamlinebreakaccident.
FortheanalysisofanyspecificaccidentorAOO, conservative or"mlimiting" valuesareused.aresultofpreviously established conservative limits,thescramworthscalculated forCycle4areboundedbythevaluesusedintheCycle3safetyanalysis.
Thepowerdependent insertion limit(PDIL)curveandCEAgroupidentification areunchanged fromthereference cycle(Reference 2).,Table5-3showsthereactivity worthsof'arious CEAgroupscalculated atfullpowerconditions forCycle4.5.1.2PowerDistribution Figures5-1through5-3illustrate theallrodsout(ARO)planarradialpowerdistributions atBOC4,MOC4andEOC4thatarecharacteristic ofthehighburnupendoftheCycle3shutdownwindow.These.planarradialpowerpeaksarecharacteristic ofthe.majorportionoftheactivecorelengthbetweenabout20and80percentofthefuelheight.Figure5-4illustrates theplanarradialpowerdistribution withintheuooer15to20oercentofthecoreproducedwiththeinsertion ofthefirstCPAregulating group,Bank7.Thispowerdistribution characteristic ofnearBUC4isbaseauponthelowburnupendoftheCycle3shutdownwindow,providing anillustration ofmaximumpowerpeakingexpectedforthisconfiguration.
HigherburnupCycle3shutdownpointstendtoreducepowerpeakinginthisupperregionofthecorewithBank7inserted.
Itisacharacteristic ofbothAROandBank7insertedconditions thattheCycle4peaksarehighestatBOC.Theradialpowerdistributions described inthissectionarecalculated datawithoutuncertaintesorotherallowances.
However,singlerodpowerpeakingvaluesdoincludetheincreased peakingthatischaracteristic offuelrodsadjoining thewaterholesinthefuelassemblylattice.ForbothDNBandkw/ftsafetyandsetpointanalysesineitherroddedorunroddedconfigurations, thepowerpeakingvaluesactuallyusedarehigherthanthoseexpectedtooccuratanytimeduringCycle4.Theseconservative values,whichareusedinSection7ofthisdocument,
.establish theallowable limitsforpowerpeakingtobeobservedduringoperation.
Therangeofallowable axialpeakingisdefinedbythelimitingconditions foroperation oftheaxialshapeindex(ASI).MithintheseASIlimits,thenecessary DNBRandkw/ftmarginsaremaintained forawiderangeofpossibleaxialshapes.Themaximumthree-dimensional ortotalpeakingfactoranticipated inCycle4duringnormalbaseload,allrodsoutoperation atfullpoweris1.85notincluding uncertainty allowances andaugmentation factors.Thisiswellwithintheoperating limitsestablished forCycle3.5.1.3SafetyRelatedData5.1.3.1EjectedCEAThemaximumreactivity worthsandplanarradialpowerpeaksassociated withanejectedCEAeventareshowninTable5-4forbothBOCandEOC.Thesevalues-encompass theworstconditions.
anticipated duringCycle4fortheplannedrangeofCycle3termination.
pointsandareboundedbythevaluesusedinthesafetyanalysisforthereference cycle.5.1.3.2DroppedCEAThelimitingparameters ofdroppedCEAreactivity worthandmaximumincreaseinradialpeakingfactorhavebeencalculated forCycle4.TheresultsindicatethatthevaluesuSedintheCycle3analysisarestillbounding.
Acomparison oftheseparameters forCycles3and4isfoundinTable5-5.
5.l.4Augmentation FactorsAugmentation factorshavebeencalculated fortheCycle4corekusingthecalculational modeldescribed inReference 5.Theinputinformation requiredforthecalculation ofaugmentation factorsthatisspecifictothecoreunderconsideration includesthefueldensification characteristics, theradialpinpowerdistribution andthesinglegappeakingfactors.Augmentation factorsfortheCycle4corehavebeenconservatively calculated bycombining forinputthelargestsinglegappeakingfactors(calculated nearendofcycle)withthemostconservative (flattest) radialpinpowerdistribution.
Thecalculations yieldnon-collapsed cladaugmentation factorsshowingamaximumvalueofl.048atthe-topofthecore.AsshowninTable5-6,theaugmentation factorsforCycle3aremorelimitingthanthevaluescalculated forCycle4.TheCycle3resultswereusedforthiscycle.8 hy5.2PHYSICSANALYSIStlETHODS5.2.l-Uncertainties intreasured PowerDistributions Thepowerdistribution measurement uncertainties whichareappliedtoCycle.4are:Fq'7.0percent,whereFq=Fxy'Fz,localpowerdensityFr=6.0percent.Thesevaluesaretobeusedformonitoring powerdistribution parameters duringoperation.
5.2.P.NuclearDesignt'jethodology
/Theanalyseshavebeenperformed inthesamemannerandwiththesamemethodologies usedforthereference cycleanalyses.
~'TABLE5-1St.LucieUnit1Cycle4PhysicsCharacteristics Dissolved BoronDissolved BoronContentforCriticalit
,CEAsMithdrawn Hotfullpower,equilibrium xenon,BOCBoroni<orthHotFullPowerBOCHotFullPowerEOCUnitsPPHPPN/%apPPH/%apReference~Cc1e'509080~Cele4107710483Reactivity Coefficients CEAsMithdrawn Moderator Temperature Coeffi-cients,HotFullPowerBeginning ofCycle(EquilibriumXe)EndofCycleDolerCoefficient HotBOCZeroPowerHotBOCFull'ower HotEOCFullPowerTotalDelayedNeutronFraction, geffBeginning ofCycleEndofCycle10-4ap/'F10-4ap/'F105ap/'F105l4p/'F105ap/'F-0.2-1.8-1.44-1.1.31~22.0060.00510.0-1.9-1.64-1.26-1.39.0063.0051NeutronGeneration Time,a*BOCEOC10-6sec10-6sec28332429~~'
TABLE5-2St.LucieUnit1LimitingValuesofCycle4CEAREACTIVITY VORTHSANDALLOWANCES,
/.dpBOCReference CycleReloadCycleEOCPeference CycleReloadCyclti'orthAvailable*WorthofallCEAsinsertedStuckCEAallowance WorthofallCEAsless,highestworthCEAstuckout10.52'7.89.72.47.33.18.311.32.98,4i<orthReuiredAllowances)
Powerdefect,HFPtoHZP{Doppler, Tavg,redistribution)
Hoderator voidsCEAbite,borondeadbandandmaneuvering bandRequiredshutdownmargin(Xdp)Totalreactivity required1.70.00.63.35.61.90.00.53~35.72.20.10.6.3.36.22.50.10.63'6:5Available i<orthLessAllowances Marginava-ilable 2.2.1.62.11~9ForeveryaccidentorA00considered inthesafetyanalysis, acalculational uncertainty of10Ãis.deductedfromtheworthavailable..
TABLE5-3ST.LUCIEUNITICYCLE4REACTIYITY k'ORTHOFCEAREGULATING GROUPSATHOTFULLPOHER,%%dDPRegulating CEAsGroup7Group6Group5Beginning ofCycle0.570'10.32EndofCycle0.800.600.44NoteYaluesshownassumesequential groupinsertion.
TABLE5-4ST.LUCIEUNITICYCLE4CEAEJECTIONDATALimiting.
ValueHaximumRadialPowerPeakFullpowerwithBank7inserted; worstCEAejectedLeropowerwithBanks7+6+5ins'erted; worstCEAejectedReference CycleSafetAnalsisValue3.608.34Cycle4Calculated Value3.026.61MaximumE'ectedCEAWorthKhp)FullpowerwithBank7inserted; worstCEAejectedZeropowerwithBanks746+5inserted; worstCEAejected.29.65.20.50Notes:Uncertainties andallowances areincludedintheabovedata.Reference cycleresultswerethoseusedintransient analysis.
TABLE5-5St.Lucie-1Cycle4FullLengthCEADropDataLimitingValuesReference Ccle~Cele4MinimumWorth%lNp.04.10MaximumPercentIncreaseinRadialPeakingFactor17Notes:(1)Houncertainties areincludedinabovedata.(2)CEAsareeitherfullywithdrawn orfullyinsertedforradialcalculations.
(3)Reference cycleresultswerethoseusedintransient analysis.
TA8LE5-6St.LucieUnit1Augmentation FactorsandGapSizesforCycle4andReference CycleCoreHeight~Percent)
CoreHeight~Inches)Reference CcleNoncollapsed CladAugmen-tationFactorGapSize~inches)ReloadCcleNoncollapsed CladAugmen-tationFactorGapSize~Inches)98.586.877.966.254.445,633.822.113.21.5134,7118.6106.590.574.462.346,230.218.12.01.0581.0531.0501.0441.0381.0331.0261.0181.0131.0032.041.801.621.381.140.960.720.480.300.061.0481.0441.0411.0361,0311.0271.0211.0151.0101.0011.741.541.381.180.970.820.620.410.260.05Note:Valuesarebasedonapprovedmodeldescribed inReference
- 5.
I'aI~III'IIaI~I~I~iiI~~I'sI~IIa~I'II'aIaoI~I~~I~'Ie~0I0~~~i~
I4~~~~0~~~~~ge I~~~lI~~~
lIIoIIIIIoa'olaiaIoIa'o)Io'aI'oIaIaI~I/II'eII05~l4~~J~ye)I'al 6.THERiLAL-HYDRAULIC DESIGll6.1Dt(BRAnalysesSteadystateD[BRanalysesofCycle4attheratedpowerlevelof2560tie(thavebeenperformed usingthesamedesigncodesasdescribed intheFSAR,Reference 6.Appropriate adjustments weremadetotheinputofthesecodestoreflecttheCycle4powerdistribution.
Table6-1containsalistofpertinent thermal-hydraulic design'arameters usedforbothsafetyanalysesandforgenerating reactorprotective systemsetpointinformation.
Theanalyseswereperformed inthesamemannerasforthereference cycle.6.2Investigations havebeenmadetoascertain theeffectoftheCEAguidetubewearproblemandthesleevingrepaironD:IORmarginsas'stablished bythistypeofanalysis.
ThefindingswerereportedtothellRCinRefrence4whichconcludethatthewearproblemandthesleevingrepairdonotadversely affectDtSRmargin.EffectsofFuelRodBowingonDi(BRtlarginEffectsoffuelrodbowingonD'<DRrerginhavebeenincorporated inthesafety.andsetpointanalysesinthesamemannerasdiscussed inReference p'.Thisreference containspenalties onminimumD/SRdueto.fuelrodbowingasafunctionofburnupgenerated usingf(RCguidelines contained inReference
- 8.
4GeneralCharacteristics TotalHeatOutput(core only)FractionofHeatGenerated inFuelRodUnitt'lg10BTU/hrReference
~Cele3~Cele42560256087378737..975,.975PrimarySystemPressureNominalMinimuminsteadystateMaximuminsteadystateDesignInletTemperature
,TotalReactorCoolantFlow(minimumsteadystate)CoolantFlowThroughCoreHydraulic Diameter(nominalchannel)AverageMassVelocityPressureDropAcrossCore(minimumsteadystateflowirreversible aPoverent',refuelassembly)
PSIAPSIAPSIA'FGPN1061b/hr1061b/hrft106lb/hr-ft2 PSI225022002300544370,000140.2*135.0*0.0442.53*10.3225022002300544370,000140.2*135.0*0.0442.53*10.3TotalPressureDropAcrossYessel(basedonnominaldimensions andminimumsteadystateflow)CoreAverageHeatFlux(accounts forabovefractionofheatgenerated infuelrodandaxialdensification factor)TotalHeatTransferArea(accounts foraxialdensification factor)FilmCoefficient atAverageConditions MaximumCladSurfaceTemperature AverageFilmTemperature Difference AverageLinearHeatRateofUndensified FuelRod(accounts forabovefractionofheatgenerated infuelrod).AverageCoreEnthalpyRisePSI33.5BTU/kr-ft2
'FoFoFkw/ft48,8605820657315.83BTU/lb65*BTU/h'r-ft2,'F 174,40033.5174,310.48,8725820657315.8265**Calculated atdesigninlettemperature, nominalprimarysystempressure.
I TABLE6-1(continued)
Calculational FactorsEngineering HeatFluxFactor,Engineering FactoronHotChannelHeatInputInletPlenumNonuniform Distribution RodPitch,BowingandCladDiameterFuelDensification Factor(axial)FuelRodBowingAugmentation FactoronFrStatistical Component ofFr995/95Confidence LevelReference
~C'cle31.031.031.051.0651.011.0181.06~Cele41.031.051.0651.011.018.1.06 7.0ACCIDENTTANDTRAtiSNTANALYSISOTHERTHAr<LOCAThepurposeofthissectionistopresenttheresultsofthesafetyanalysis(otherthanLOCA)forSt.LucieUnit1,Cycle4at2560t~iHTcontaining fuelassemblies with3.65w/oenrichment.
Theeventsconsidered forthisanalysisarelistedinTable7.1.Thesearethedesignbasiseventsfortheplant.Theseeventscanbecategorized intothefollowing groups:l.Anticipated Operational Occurrences forwhichtheReactorProtection SystempreventstheSpecified Acceptable FuelDesignLimits(SAFDLs)frombeingexceeded; 2.Anticipated Operational Occu)rencesforwhichtheinitialsteadystateoverpower marginmustbemaintained inordertopreventtheSAFDLsfrombeingexceeded; 3.Postulated Accidents.
EachoftheeventslistedinTable7-1hasbeenreviewedforCycle4todetermine ifanexplicitreanalysis wasrequired'.
Table7-1indicates theanalysisstatusofeachevent.Table7-2presentsthecoreparameters used.intheCycle4analysisandcomparesthemtothereference cycle.Thereviewofeachdesignbasisevent(DBE)entailedacomparison betweenallthecurrentandreference cyclekeytransient paramet'ers thatsignificantly impacttheresultsofanevent.Thereference analysisforeacheventistheanalysisuponwhich'helicensing ofSt.LucieUnit1,Cycle3wasbased.llhenthecurrentcyclevaluesofkeyparameters foraparticular eventareboundedby(conservative withrespectto)thereference cycle,noreanalysis isrequiredorperformed.
Theresultsofthereviewarethatthekeyparameters foralltheDBEsforCycle4operation arethesameas,ornoworsethan,thespecified reference cycleinputparameters, exceptforthefollowing:
1.Highercriticalboronconcentration 2.SeizedRotorpincensus3.CEAEjectionpincensusAreanalysis"of theBoronDilutioneventwasperformed todetermine theeffectsofthemoreadverseboronparameters forCycle4.TheseizedrotoreventandCEAejectioneventwerereanalyzed toevaluate'the, impactofmoreadversepin.censusfor,thesepostulated events.ForallDBEsotherthanthosereanalyzed,
'theSt.LucieUnit1safetyanalyses-forpreviousrelopdcyclelicensesubmittals bouncLtheresultsthatwouldb'eobtainedforUnit"1,Cycle4anddemonstrate safeoperation ofSt.LucieUnit1Cycle4at2560llWTwiththehigherenrichment.
fuel.Insummary,theresultsofthereanalysis demonstrate thattheconclusions reachedinthereference cycleanalysisforeacheventremainvalidforCycle4.
TABLE7-1St.LucieUnit1,Cycle4EventsConsidered inTransient andAccidentAnalysisAnticipated Operational Occurrences forwhichtheRPSAssuresnoViolation ofSAFDLs:I'lliS<<ControlElementAssemblyWithdrawal BoronDilutionSt~tr)pofanInactiveReactorCoolantPumpExcessLoadLossofLoadLossofFeedwater FlowExcessHeatRemovalduetoFeedwater tlalfunction Rea'ctorCoolantSystemDepressurization LossofCoolantFlowLossofACPower'-NotReanalyzed Reanalyzed NotReanalyzed HotReanalyzed NotReanalyzed HotReanalyzed NotReanalyzed NotReanalyzed HotReanalyzed NotReanalyzed Anticipated Operational Occurrences whichareDependent onInitialOverpower MarginforProtection AgainstViolation ofSAFDLs:LossofCoolantFlowLossofACPowerFullLengthCEADropPartLengthCEADropPartLengthCEANalpositioning Transients Resulting fromMalfunction ofOneSteamGenerator HotReanalyzed NotReanalyzed NotReanalyzed HotReanalyzed NotReanalyzed NotReanalyzed Postulated Accidents:
CEAEjectionSteamLineRuptureSteamGenerator TubeRuptureSeizedRotorReanalyzed NotReanalyzed NotReanalyzed Reanalyzed 1RequiresLowFlowTrip.
TABLE7-2St.Lucie1CoreParameters InputtoSafetyAnalyses'h sicsParameters PlanarRadialPeakingFactorsUnitsReference Cycle4~C1I1VForDNBMarginAnalyses(Fr)UnroddedRegionBank7Inserted1.591.801.591.80ForPlanarRadialComponent of3-DPeak(Fx)(kw/ftLimitAnalyses)
UnroddedRegionBank7InsertedPeakAugmentation FactorModerator Temperature Coefficient ShutdownMargin(YalueusedinZeroPower)(SLB)(1loop/2loop)1.581.821.0711.581.821.071.10bp/F-2.5~+.5-2.5~+.-4.1/-3.3-4.1/-3.SafetParameters PowerLevelMaximumSteadyStateCoreInletTemperature MinimumSteadyStateRCSPressureReactorCoolantCoreFlowFullPowerAxialShapeIndexLimitMaximumCEAInsertion atFullPowerMinimumAllowable InitialPeakLinearHeatRatefortransients otherthanLOCASteadyStateLinearHeatRatetoFuelCenterline MeltCEADropTimefromRemovalofPowerHolding.Coilsto90%Insertion ThreePumpPlenumFactorNHtoFpsia10lb/hrIp%Insertion ofGroup7kw/ftkw/ftSec2611'442200134.9"0232516.021,03.11.0926115442200.134.9~2316.021.03.11.09 J
TABLE7.1-1AssumedInputParameters forBoronDilutionAnalysisParameter Ref.Cycle~212~Cele4CriticalBoronConcentration, PPt1(AllRodsOut,ZeroXenon)PowerOperation StartupHotStandbyHotShutdownColdShutdownRefueling 120013001300130013001200133014201420142014201280InverseBoronWorth,PPt</%apPowerOperation StartupHotStandbyHotShutdownColdShutdownRefueling70655555959070707070 7.1BORON'DILUTION EVENTTheBoronDilutioneventhas,beenreanalyzed forCycle4duetoincreases inthecriticalboronconcentrations (SeeTable7.1-1forcomparison betweenCycle2andCycle4boronparameters.
Thisisthesamereference cyclethatwascitedintheCycle3licensesubmittal).
Thisincreaseincriticalboronconcentration isoffsetbyacorresponding increaseintheminimuminverseboronworth.Thus,thetimetodilutetocriticality forCycle4isnolessthanthetimecalculated forthereference cycle.TheBoronDilutioneventatpowerproducesaslowpowerandtemperature increasewhichcausesanapproachtoboththeDNBRandkw/ftSAFDLs.SincetheTtl/LPtripsystemmonitorsthetransient behaviorofcorepowerlevelandcoreinlettemperature, theTt1/LPtripassuresthattheDNBRSAFDLisnotexceededforpowerincreases withinthesettingoftheVariableHighPowerLeveltrip;forpowerexcursions inexcessoftheVariableHighPowerLeveltrip,areactortripisactuated.
Theapproachtothekb/ftSAFDListerminated byeithertheLocalPowerDensity-High trip,VariableHighPowerLeveltriportheDNBRrequiredtripdiscussed above.Forborondilutioninitiated fromhotzeropower,critical, thepowertransient resulting fromtheslowreactivity insertion ratecharacterizing theborondilutiontransient isterminated bytheVariableHighPowerLeveltrippriortoapproaching theSAFDLs.There-evaluation showsthetimetocriticality isgreaterthan15minutesforborondilutions initiated fromtheStartup,HotStandby,HotShutdown, andColdShutdownoperational modes.Forthere-fuelingmode,thetimetocriticality isgreaterthan30minutes.Consequently, theconclusions reachedforCycle2remainvalidforCycle4.
7.2SEIZEDROTOREVENiTheSeizedRotorEventwasreanalyzed forCycle4toevaluatethe'numberoffuelpinspredicted toexperience DflBduetoaslightlymoreadversepincensusdistribution forCycle4thanforthereference cycle.(Reference cycleforthiseventisCycle3.)Thetransient behaviorofthiseventisthesameasforthereference cyclesinceall'hetransient relatedparameters arethesameas,orconservative withrespectto,thereference cycle.Therefore, onlyarecalculation ofthenumberoffuelpinspredicted toexperience DNBwasperformed usingthecycle4pincensus.Theresultsshowthat,forCycle4,thenumberoffuelpinspredicted toexperience DNBis1.05/,ascomparedtothe0.99~reportedforCycle3.Therefore, theconclusion reachedinthereference cyclethatonlyaverysmallnumberofthefuelpinswouldexperience DNB'emains validforCycle4.
7.3CEAEJECTIONEVENT0TheCEAEjectionEvent,wasreanalyzed forCycle4toevaluatethenumberof'uelpins.predicted toexperience incipient centerline
'eltduetoaslightlymoread'versepincensusdistribution forCycle4thanforthereference cycle.(Reference cycleforthiseventisCycle3.)Inthereference cycle,nopinwaspredicted toexceedthecriterion forcladdamage(i.e.,averagedeposited energyof200cal/gm).Thetransient behaviorofthiseventisthe.sameasforthereference cyclesinceallthetransient relatedparameters arethesameas,orconservative withrespectto,thereference cycle.Therefore, onl'yarecalculation ofthenumber,offuelpinspredicted toexperience incipient centerline meltingwasperformed usingthecycle4pincensus.Theresultsshowthat,forCycle4,thepredicted fractionoffuelpinsexpectedtoexperience incipient centerline meltingforthetransient initiated atfullpoweris0.045.Forthereference cycleanalysis, acalculated fractional valueof0.028ofthefuelpinswerepredicted toexpelienceinciointcenterline meltingatfullpower.However,sincenofuelpinispredicted toexperience claddamage,theconclusion reachedinthereference cycleremainsvalid.
References (Sections Ithrough7)1.CEN-79-P, "ReactorOperation WithGuideTubeHear",February3,19782.Letter,RobertE.Uhrig(FPSL)toVictorStello(NRC),datedFebruary22,1979,"St.LucieUnit1DocketNo.50-335ProposedAmendment toFacilityOperating License-.DPR-67" 3.5.6.CENPD-187, "CEPANmethodofAnalyzing CreepCollapseofOvalCladding",
June1975CEN-80(N)-P; "Millstone Unit2.ReactorOperation Withttodified CEAGuideTubes",February8,1978CENPD-139, "C-EFuelEvaluation HodelTopicalReport",July1,1974St.LucieNuclearPowerPlant(Formerly Hutchinson Island)UnitOne,FinalSafetyAnalysisReport,insupportofDocketNo.50-3357,Supplement 3-P(Proprietary) toCENPD225P,"FuelandPoisonRodBowing",June1979LetterfromD.B.Vassallo(NRC)toA.E.Scherer(C-E)datedJune12,1978.
St.LucieICycle4ECCSPerformance ResultsIINTRODUCTION ANOSUt<HARYTheECCSperfora>ance evaluation forSt.LucieICycle4,presented herein,'emonstrates appropriate conformance withtheAcceptance CriteriaforLight-Water-Cooled Reactorsaspresented in10CFR50.46
.Theevaluation (1)demonstrates acceptable ECCSperformance atapeaklinearheatgeneration rate(PLHGR)of14.8kw/ftandapowerlevelof2611that(102Ãof2560t'lwt).Themethodofanalyisandresultsarepresented inthefollowing sections.
HETHODOFANALYSISThisanalysiswasperformed usingtheapprovedC-ELargeBreakEvaluation (2)tlodel.Themodelwasusedtore-evaluate thelimitinglargebreakLOCAECCSperformance.
Theblowdownandrefill-reflood parameters ofthepreviouscycleremainunchanged.
Therefore, onlySTRIPINII()calculations werenecessary toaccountforthedifferent pinconditions.
Burnupdependent calculations wereperformed usingtheFATESand(5)STRIKIN-II codestodetermine thelimitingcondition fortheECCSperformance analysis.
Thebreaksizeandtypeanalyzed, 0.8DES/PD*,isthesameaswasanalyzedinpreviouscycles.Forconservatism, thePARCHcodewasnotutilizedintheCycle4evaluation
~ThelaterefloodheattransferbenefitfromtheuseofthePARCHsteamcoolingheattransferwouldhavereducedthepeakcladtemperature reportedherein.*0.9xDoubleEndedSlotBreakintheReactorCoolantPumpDischarge Leg O
8.2RESULTSANDCONCLUSIONS Table1presentstheanalysisresultsforthelimiting0.8DES/PDbreak.Alistofthesignificant parameters displayed graphically ispresented inTable2.Asummaryofthefuelandsystemparameters isshowninTable3.Ascanbeseenfromtheresults,theworstbreakanalysisresultsinapeakcladtemperature of1986'Fwhichiswellbelowtheciiterialimit.Thelocalandcorewid(zirconium oxidation percentages are10.49%and0.60'i,,respectively.
Hence,opera-stionatapeaklinearheatgeneration rateof14.8kw/ftandatapowerlevelof2611Hwt(102Kof2560Hwt)willresultinacceptable ECCSperformance.
3COHPUTERCODEVERSIONIDEHTIFICATION Thefollowing NRC-approved versionofCombustion Engineering ECCSEvaluation I'1odelcomputercodewasusedinthisanalysis:
STRIKIH-II:
VersionNo.77036 REFERENCES (Section8)l.Acceptance CriteriaforEmergency CoreCoolingSystemsforLight-MaterCooledNuclearPowerReactors, FederalRegister, Vol.39,No.3-Friday,January4,1974.2.CENPD-132, "Calculative NethodsfortheCELargeBreakLOCAEvaluation Model",August1974(Proprietary).
CENPD-132, Supplement 1,"Calculational MethodsfortheCELargeBreakLOCAEvaluation Model",December1974(Proprietary).
CENPD-132, Supplement 2,"Calculational methodsfortheCELargeBreakLOCAEvaluation Model",July1975(Proprietary).
3.LetterfromFPSLtollRCtransmitting St.LucieICycle3ECCSperformance results(February 22,1979;L-79-45),
4.CENPD-135, "STRIKIN-II, ACylindrical GeometryFuelRodHeatTransferProgram",
August1974(Proprietary).
CENPD-135, Supplement 2,"STRIKIN-II, ACylindrical GeometryFuelRodHeatTransferProgram(Modifications),
February1975(Proprietary).
CENPD-135, Supplement 4,"STRIKIN-II, ACylindrical GeometryFuelRodHeatTransferProgram",
August1976(Proprietary).
CENPD-135, Supplement 5,"STRIKIN-II, ACylindrical GeometryFuelRodHeatTransferProgram",
April1977(Proprietary).
5.CENPD-139, "CEFuelEvaluation l1odel",July1974(Proprietary).
6.CENPD-138, "PARCH-AFORTRAN-IV DigitalProgramtoEvaluatePoolBoiling,AxialRodandCoolantHeatup",August1974(Proprietary).
CENPD-138, Supplement 2,"PARCH-AFORTRAN-IV DigitalProgramtoEvaluatePoolBoiling,AxialRodandCoolantfleatup",
January1977(Proprietary).
TABLE1SummaryofResultsforSt.LvcieICycle4ECCSPerformance ResultsBreakPeakClad~TtTimeof~ttTTimeofCladRutureOxidation
/LocalCoreBi-de0.8DES/PD1986'F249.Zsec55.32sec10.49-(.60.
St.LucieICycle4Variables PlottedasaFunctionofTimeVariables
~FiureD~esinationPeakCladTemperature HotSpotGapConductance PeakLocalClad.Oxidation CladTemperature, Centerline FuelTemperature, AverageFuelTemperature andCoolantTemperature forHottestNodeHotSpotHeatTransferCoefficient HotRodInternalGasPressure~13 VaTABLE3St.LucieICycle4GeneralSystemParameters Q~uantitValueReactorPowerLevel(102%ofNominal)AverageLinearHeatGeneration Rate(102KofNominal)PeakLinearHeatGeneration RateGapConductance atPLHGRFuelCenterline Temperature atPLHGRFuelAverageTemperature atPLHGRHotRodGasPressureHotRodBurnup26116.093214.815273510.32195.61035.81488Hwtkw/ftkw/ftBTU/hrft'FoFoFpsiat@lD/t)TU IoIIIIIIIllew~~I<<IIatll~ll<<llllII~II 1ollaIlIII'i~'l~~a~IggI1IallallSlIISl~IIIl~II k~I'I'1)IO'I'III'J~tlSl~IIII 0e
~lg0gIIIt~~g~IIjSSSillSISSlSl
~II~IP~II~IiIIlIIIIIIIII I'I'IIIL~)IIoiloilIIIIIIIl 0Pt4]lIr