PerformanceimprovementanalysisofboilingwaterreactorsbyincorporationofhydridefuelOriginalResearchArticle

Thefeasibilityofimprovingtheneutroniccharacteristicsofboilingwaterreactors(BWR)byusingU–Zrhydridefuelisstudied.SeveralmodifiedBWRfuelassemblydesignsareconsidered.Theseincludedesignsinwhichhydridefuelrodsreplacewaterrodsonly,replacewaterrodsandafractionoftheoxidefuelrods,replaceoxidefuelintheupperhalfofallthefuelrods,andreplacealltheoxidefuelintheassembly.ItisfoundthatreplacementofatleasthalfoftheoxidefuelrodsinthefuelassemblybyU–ZrH1.6fuelmightsimultaneouslyimprovetheperformanceofBWRinthreeways:(a)Increasingtheenergyextractedperfuelassemblyandthecyclelengthbyupto∼10%.(b)ReducingtheuraniumoreandSWUrequirementsbyapproximately10%.(c)Reducingthenegativevoidcoefficientofreactivityby,atleast,50%.ItisalsofoundthatreplacementofalltheoxidefuelbyhydridefuelopensinterestingnewoptionsforthedesignofBWRfuelassemblies.Thenetresultmightbesimplifiedassemblydesignsthatcangeneratesignificantlymoreenergywhilefeaturingsmallnegativevoidcoefficientofreactivity.U–ThH2fuelappearstobeevenmorepromisingthanU–ZrH1.6.Forthepotentialbenefitsfromhydridefueltoberealized,acladmaterialthatisnotpermeabletohydrogenandisnotasneutronabsorbingasstainlesssteelneedstobedeveloped.