A neutronic benchmark specification and COMET solution for the Advanced Burner Test Reactor

This work describes a stylized three dimensional benchmark problem based on Argonne National Laboratory's conceptual Advanced Burner Test Reactor design. This reactor is a sodium cooled fast reactor designed to burn recycled fuel to generate power while transmuting transuranic waste. The specification includes heterogeneity at both the assembly and core levels while the geometry and material compositions are both fully described. Material nuclear data is provided in the form of a set of 15 group macroscopic cross sections which were developed so that the benchmark specification could be used for transport code method verification. Using this benchmark and 15 group cross sections, the Coarse Mesh Transport Method (COMET) code was verified against the Monte Carlo code MCNP. Results were generated for three separate core cases: control rods out, near critical, and control rods in. Eigenvalue comparison results between COMET and MCNP are within 50 pcm for all three cases, well within two standard deviations of the stochastic uncertainty of the solution methods. The fission density results are highly accurate with a pin fission density average discrepancy between COMET and MCNP of less than 0.5% for each model.