Benchmark description of an advanced burner test reactor and verification of COMET for whole core criticality analysis in fast reactors

Abstract

This work developed 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 long term waste. The specification includes heterogeneity at both the assembly and core levels while the geometry and material compositions are both fully described. After developing the benchmark, 15 group cross sections were developed so that it could be used for transport code method verification. Using the aforementioned benchmark and 15 group cross sections, the Coarse-Mesh Transport Method (COMET) code was compared to Monte Carlo code MCNP5 (MCNP). Results were generated for three separate core cases: control rods out, near critical, and control rods in. The cross section groups developed do not compare favorably to the continuous energy model; however, the primary goal of these cross sections is to provide a common set of approachable cross sections that are widely usable for numerical methods development benchmarking. Eigenvalue comparison results for MCNP vs. COMET are strong, with two of the models within one standard deviation and the third model within one and a third standard deviation. The fission density results are highly accurate with a pin fission density average of less than 0.5% for each model.