b'3.5 PERFORMANCE ASSESSMENTResults of a Trade Study on Design and Fabrication Candidatesfor Sodium Free Metallic FuelPrincipal Investigator: Nicolas WoolstenhulmeTeam Members/ Collaborators: Kevan Weaver, Randall Fielding, Douglas Porter, Colby Jensen, Daniel Wachs, Steven HayesM etallic fuel systems offerProject Description:several beneficial featuresIn product development few for sodium cooled fastjunctures are as pivotal as design reactors (SFR). The classical metallicconcept selection. An engineering fuel design uses an internal liquidtrade study is a structured way of sodium bond (between fuel slugassessing design options and deciding and cladding inner diameter) whichon preferred candidates. Sometimes offers significant thermal fuelreferred to as optioneering, a trade performance benefits. However,study endeavors to reduce subjectivity this design feature has undesirableand avoid classical problems in impacts such as requiring reactivedesign decisions such as favoring metal handling in fuel fabrication,concepts that just seem better or that creating modest detriments toare simply preferred by an influential reactor neutronics, and increasingmember of the team. In this case a chemical reactivity hazards indecision matrix method was used shipping/storage scenarios. Thewhere criteria were listed, concepts latter point is particularly importantwere generated, and candidates were in SFRs designed for once-throughassessed by expert team ranking. This fuel cycles rather than continuousprocess was semi-quantitative and fuel recycle. An engineeringrequired expert judgment, so it was trade-off study was undertaken tostill somewhat subjective, but the evaluate fuel design and fabricationvarious viewpoints expressed and process options for developing areconciled during the ranking added so-called sodium-free fuel (SFF)confidence to the decision reached.able to eliminate these undesirable features while still retaining manyAccomplishments:of metallic fuels most beneficialThe SFF trade study was performed properties. The primary purposeover the course of a few months in of this trade study was to rank and2022 using several team sessions, prioritize future research tasks inrather than a single long session, order to accelerate overall develop- in order to give time in between ment cycle for deploying SFF. for team member to generate new concepts. This approach was 136 2022|AFC ACCOMPLISHMENTS'