Feasibility studies for simultaneous irradiation of NBSR and MITR fuel elements in the BR2 reactor

The BR2 reactor is involved in preliminary neutronics feasibility studies for irradiation of four Design Demonstration Element (Dde) tests foreseen in the US High Performance Research Reactor (US HPRR) conversion program: MURR, MITR, NBSR and HFIR. The purpose of the irradiation will be to qualify the new Leu fuel material for each Dde Lead Test Assembly in the BR2 reactor at conditions that are similar for the reactor of origin. The present paper focuses on the preliminary feasibility scenarios for simultaneous irradiation of two Dde s: the MITR and the NBSR Lead Test Assemblies in the BR2 reactor. The MITR and the NBSR fuel elements will be loaded in the 200 mm diameter channels (H5 and H3). In order to mimic the irradiation conditions for each Dde in the BR2 reactor as in the original reactors, a number of optimization scenarios are considered. The flux and burn-up calculations are performed using the fully automatic option of the MCNP6/CINDER90 code. (Author)