2017 | AFC ACCOMPLISHMENTS 153 Accomplishments: We have improved BISON capability for metallic fuels significantly this year. The validated specifies distribution kernel for U-Zr fuel is implemented. Short-term solutions to numerical problems encountered in stress aware swelling model are developed. A mechanistic gas release model is implemented.A critical review of fuel- clad-chemical interactions along with modeling requirements is published. The mechanism of lanthanide transport is studied experimentally (Nuclear Energy University Project (NEUP) collaboration) and using simulations.A new staged Bayesian calibration approach allowing us to see deficiencies in modeling and developing state aware mitigation strategy is used to calibrate the capability.We apply the current capability to the fuel rodT179 (U-19Pu-10Zr) to demonstrate how an advanced simulation aided metallic fuel can be designed. Two cases were run to compare with the baselineT179 simulation (1, 2). The “axial shift” case utilizes a power profile that is shifted from the bottom of the core to the top.The second case represents changing the fabrication of the fuel rod to create a linearly varying the concentration of plutonium as a function of axial height. Figure 1. Simulation results at end-of-life showing Zr redistribution in a 2D-RZ slice of the fuel (Left), centerline temperature (Right Top), and centerline Zr atom fraction (Right Bottom).