EffectsoftuberupturemodelingandtheparametersontheanalysisofmultiplesteamgeneratortuberuptureeventprogressioninAPR1400OriginalResearchArticle

Amultiplesteamgeneratortuberupture(MSGTR)eventinAPR1400hasbeeninvestigatedusingthebestestimatethermalhydraulicsystemcode,MARS1.4.Theeffectsoftheparameterssuchasthenumberofrupturedtubes,rupturelocation,affectedsteamgeneratorontheanalysisoftheMSGTReventinAPR1400areexamined.Inparticular,tuberupturemodelingmethods,singletubemodeling(STM)anddoubletubemodeling(DTM),arecompared.TheAPR1400isfoundtohavethecapabilityofallowingmorethan30mintooperatorsfortheMSGTReventoffivetubes.TheeffectsofrupturelocationontheMSSVlifttimeisnotsignificantinthecaseofSTM,buttheMSSVlifttimefortube-topruptureisfoundtobe25.3%largerthanthatforruptureatthehot-legsidetubesheetinthecaseofDTM.TheMSSVlifttimeforthecasesthatbothsteamgeneratorsareaffected(4C5x,4C23x)arefoundtobelargerthanthatofthesinglesteamgeneratorcases(4A5x,4B5x)duetoabifurcationoftheprimaryleakflow.ThedischargecoefficientofCdisfoundtoaffecttheMSSVlifttimeonlyforasmallervalueof0.5.ItisfoundthatthemostdominantparametergoverningtheMSSVlifttimeistheleakflowrate.Whetheranymodelingmethodisused,itgivesthesimilarMSSVlifttimeiftheleakflowrateisclose,exceptinthecasewherebothsteamgeneratorsareaffected.Therefore,thesystemperformanceandtheMSSVlifttimeoftheAPR1400arestronglydependentonthebreakflowmodelusedinthebestestimatesystemcode.