Neutronic study of extended DONES irradiation module

Highlights: • DONES (DEMO Oriented Neutron Source) has been conceived as a simplified of IFMIF. • Neutron transport calculations were performed to evaluate the irradiation parameters in HFTM zone. • Neutron fluence rate gradients are lower than 25% in the most volume of HFTM of DONES-IFMIF. • Enlarge the experimental irradiation volume allows to extend the irradiation experiments to other materials, different of steels. - Abstract: IFMIF is considered as one of the main pillars in the international fusion program. Its double deuteron beam 125 mA each will produce enough rate of damage behind the lithium target to make available in a few years information on materials damage at DEMO relevant doses. Furthermore the stripping reaction D-Li will produce in Fe-based materials under study a production of He and H similar to those expected in fusion reactor. DONES (DEMO Oriented Neutron Source) has been conceived as a simplified IFMIF-like plant to provide in a reduced time scale and with a reduced budget – both compared to IFMIF- the basic information on materials damage. In this work, radiation conditions behind the irradiation module, the so-called High Flux Test Module (HFTM), are analyzed with a double objective. First objective is to assess the impact of the second irradiation module on the material irradiation effects in the HFTM due to its potential use as optimization tool for the damage dose and gas production in the specimens. Second objective is to assess on the potential use of that volume for irradiation of additional specimens beyond the HFTM. Then, neutron transport calculations have been performed in order to evaluate the impact on the irradiation effects on the HFTM and to determine the radiation level in the experimental samples of the new module.