SeverefueldamageexperimentsperformedintheQUENCHfacilitywith21-rodbundlesofLWR-typeOriginalResearchArticle

TheobjectiveoftheQUENCHexperimentalprogramattheKarlsruheResearchCenteristoinvestigatecoredegradationandthehydrogensourcetermthatresultsfromquenching/floodinganuncoveredcore,toexaminethephysical/chemicalbehaviorofoverheatedfuelelementsunderdifferentfloodingconditions,andtocreateadatabaseformodeldevelopmentandimprovementofseverefueldamage(SFD)codesystems.Thelarge-scale21-rodbundleexperimentsconductedintheQUENCHout-of-pilefacilityaresupportedbyanextensiveseparate-effectstestprogram,bymodelingactivitiesaswellasapplicationandimprovementofSFDcodesystems.InternationalcooperationsexistwithinstitutionsmainlywithintheEuropeanUnionbut,e.g.alsowiththeRussianAcademyofScience(IBRAE,Moscow)andtheCSARPprogramoftheUSNRC. Sofar,11experimentshavebeenperformed,twoofthemwithB4Cabsorbermaterial.Experimentalparameterswere:thetemperatureatinitiationofreflood,thedegreeofpre-oxidation,thequenchmedium,i.e.waterorsteam,anditsinjectionrate,theinfluenceofaB4Cabsorberrod,theeffectofsteam-starvedconditionsbeforequench,theinfluenceofairoxidationbeforequenchandboil-offbehaviorofawater-filledbundlewithsubsequentquenching. TheworkisfocusedonseverefueldamagebehaviorforassemblieswithandwithouttheB4Cabsorber.AnoverviewoftheQUENCHprogramwithitsorganizationalstructureandthedescriptionofthetestfacilityisalsopresented.