One-andtwo-dimensionalstandingpressurewavesandone-dimensionaltravellingpulsesusingtheUS-NRCnuclearsystemsanalysiscodeTRACEOriginalResearchArticle

Avarietyofnuclearsystemtransientscanleadtorapidandlargelocalpressurechangesthatpropagatealongthehydraulicsystematthespeedofsound,bothinsinglephaseandintwo-phasefluids.Becauseoftherelevanceforsafetyissues,nuclearsystemcodeslikeTRACEneedtobeassessedwithrespecttotheircapabilitiestopredictpressurewavebehaviour.Therefore,wehaveanalyzedthepropagationofpressurewavesinone-dimensionalandtwo-dimensionalconfigurations,i.e.apipeandaslab,filledwithliquidwater.Thepressurewavesaredrivenbyone-sidedpressureboundaryconditions,intheone-dimensionalcaseofharmonicorGaussianshapeandinthetwo-dimensionalcasealsoofharmonicshape.Theselectedharmonicpressureboundaryconditionsleadtostandingpressurewaves,whileusingtheGaussianshapeboundaryconditionsone-dimensionalpressurepulsesareinjectedandpropagatethroughthepipe.TheagreementoftheTRACEresultswiththeanalyticalsolutionsare,ingeneralverygoodtogoodfortheone-dimensionalcaseswithrespecttothepressuremaximaandasmalldifferenceisonlyobtainedinthewavespeed.