Global Flux Calculation for IFMIF-DONES Test Cell Using Advanced Variance Reduction Technique

Global neutron flux and dose maps for the test cell (TC) of the IFMIF-DONES (International Fusion Materials Irradiation Facility–DEMO Oriented NEutron Source) have been calculated applying the advanced variance reduction tool ADVANTG. The neutronics model of the TC has been updated to the current IFMIF-DONES design of the target assembly, the high flux test module, and the lithium quench tank as well as the TC surrounding rooms. A weight-window (WW) mesh has been produced using ADVANTG with the well-configured setups for IFMIF-DONES conditions. This WW mesh has been adjusted to achieve reasonably good statistics for the global flux mesh tally. It is concluded that the thickness of the beam upstream and lateral wall can be reduced by 0.5 m without strongly affecting the shielding performance. The neutron streaming through the gaps of the shielding plugs to the access cell above the TC requires local shielding to allow frequent access during operation.