Title of article
BorondilutiontransientsduringnaturalcirculationflowinPWR—ExperimentsandCFDsimulationsOriginalResearchArticle
Author/Authors
ThomasH?hne، نويسنده , , S?renKliem، نويسنده , , UlrichRohde، نويسنده , , Frank-PeterWeiss، نويسنده ,
Issue Information
روزنامه با شماره پیاپی سال 2008
Pages
9
From page
1987
To page
1995
Abstract
Coolantmixinginthecoldleg,downcomerandthelowerplenumofpressurizedwaterreactorsisanimportantphenomenonmitigatingthereactivityinsertionintothecore.Therefore,mixingofthede-boratedslugswiththeambientcoolantinthereactorpressurevesselwasinvestigatedatthefourloops1:5scaledRossendorfcoolantmixingmodel(ROCOM)mixingtestfacility.Inparticularthermalhydraulicsanalyseshaveshown,thatweaklyboratedcondensatecanaccumulateinthepumploopsealofthoseloops,whichdonotreceiveasafetyinjection.Afterrefillingoftheprimarycircuit,naturalcirculationinthestagnantloopscanre-establishsimultaneouslyandthede-boratedslugsareshiftedtowardsthereactorpressurevessel(RPV).
IntheROCOMexperiments,thelengthoftheflowrampandtheinitialdensitydifferencebetweentheslugsandtheambientcoolantwasvaried.Fromthetestmatrixexperimentswith0resp.2%densitydifferencebetweenthede-boratedslugsandtheambientcoolantwereusedtovalidatetheCFDsoftwareANSYSCFX.TomodeltheeffectsofturbulenceonthemeanflowahigherorderReynoldsstressturbulencemodelwasemployedandameshconsistingof6.4millionhybridelementswasutilized.OnlytheexperimentsandCFDcalculationswithmodeleddensitydifferencesshowstratificationinthedowncomer.Dependingonthedegreeofdensitydifferencesthelessdenseslugsflowaroundthecorebarrelatthetopofthedowncomer.Attheoppositeside,thelowerboratedcoolantisentrainedbythecoldersafetyinjectionwaterandtransportedtothecore.ThevalidationprovesthatANSYSCFXisabletosimulateappropriatelytheflowfieldandmixingeffectsofcoolantwithdifferentdensities.
Journal title
Nuclear Engineering and Design Eslah
Serial Year
2008
Journal title
Nuclear Engineering and Design Eslah
Record number
895153
Link To Document