Assessment of the Effects of Anisotropy in TRIGA Based on 3D-AGENT Methodology

The neutronics characterization of The University of Utah TRIGA reactor core focused at evaluating the effects of anisotropic neutron scattering is based on 3D AGENT methodology. The AGENT methodology is based on method of characteristics with exact modeling of geometry and material distribution in the reactor cores. This feature is unique to deterministic codes worldwide and is based on the originally developed R-function solid modeler. The anisotropic correction to neutron transport in 3D hexagonal and square reactors as implemented in AGENT, provides highly accurate solution with no limitations to core configuration or the degree of anisotropic scattering terms. In testing this new methodology on TRIGA type reactors, we conclude that the AGENT deterministic solution with P₂ anisotropic scattering approximation provides fully comparable solution to the MCNP5 but with 93% CPU-time reduction.