A Comparison of Two Versions of a Proposed Test Reactor Using the MCNP Neutronics Code

The Broad-Application Test Reactor has been proposed for testing and isotope production missions in the early twenty-first century. Two conceptual designs, both employing metal plate fuel, light water coolant, and a heavy-water primary or secondary reflector region, survived an initial screening process. The Monte Carlo neutronics code (MCNP) was used to select one of these designs for future development. For each design, alternative fuel and pressure vessel materials were considered, and a preferred material was identified for each of the candidate designs. The design judged superior contains seven test regions, each surrounded by Zircaloy fuel annuli and enclosed by its own separate Zircaloy pressure boundary tube.