b'3.5 COMPUTATIONAL ANALYSISIrradiation Testing of Slotted Metallic FuelPrincipal Investigator: Pavel Medvedev, INLFigure 1. Four-slotted fuel before and after irradiation. Figure 2. Porosity distribution in four-slotted slotted fuel after irradiation.I rradiation testing of slotted metallic fuel has been proposed by the Advanced Fuel Campaign (AFC) in order to develop high burnup fuel designs (INL/EXT-18-45933).Pre-fabricated fuel slots are designed to accommodate fuel swelling. Project Description: The key challenge is understanding Figure 3. Two-slotted fuel before and after irradiation. the evolution of the fuel slug geom-etry during irradiation. Closure of prefabricated slots without significant cladding strain is a desired behavior. Excessive cladding strain due to fuel swelling occurs if slots fail to close, signifying undesired behavior.Slotted Fuel Deformation BISON simulation of U-10Zr sodium bonded slotted fuel irradiation predicted favorable behavior under Figure 4. Nominal cladding thickness.Figure 5. Reduced (50%) claddingprototypic conditions thickness.Swelling and creep of the fuel cause prefabricated slots to close without significant cladding deformation224 2019|AFC ACCOMPLISHMENTS'