The Divertor Plasma Facing Components (PFCs) of a fusion reactor play a key role in the removal of plasma power exhaust and impurity particles, being exposed to very intense thermal load and high neutron irradiation, which can severely compromise their functioning capability. Therefore, the choice of the plasma facing materials (PFMs) is a fundamental aspect in the design of these components. Tungsten is presently the main candidate being characterised by several advantages from a thermo-physical point of view, but also some drawbacks (e.g. significant activation under neutron irradiation). Neutronics assessment plays a key role in the design of these critical components and in the choice of the most suitable PFMs. Detailed nuclear analyses have been performed by implementing, for the first time, heterogeneous models of the actual ITER-Like PFCs geometry [1,2], aimed to assess the impact of neutronics and activation issues on design, lifetime, operations and safety of the PFCs of DEMO divertor and to provide outcomes useful in the PFCs selection concept, under study within the EUROfusion WPDIV-2 project. In particular way, the effects of two different blankets (WCLL and HCPB) on W activation and the impact of three different W compositions and chromium, have been compared. Three-dimensional neutronic analyses have been performed with the MCNP5 Monte Carlo [3] using the reference JEFF 3.3 nuclear data libraries [4] to calculate neutron spectra in PFCs subcomponents. Activation analysis has been performed with FISPACT II inventory codes [5] to assess the specific activity, decay heat and contact dose at the end of DEMO-1 operations. The calculations have been carried-out on ENEA HPC CRESCO6 cluster (Ponti et al., 2014).
Neutronics analysis and activation calculation for tungsten used in the DEMO divertor targets: A comparative study between the effects of WCLL and HCPB blanket, different W compositions and chromium
Flammini D.;Mariano G.;Mazzone G.;Moro F.;Villari R.;
2021-01-01
Abstract
The Divertor Plasma Facing Components (PFCs) of a fusion reactor play a key role in the removal of plasma power exhaust and impurity particles, being exposed to very intense thermal load and high neutron irradiation, which can severely compromise their functioning capability. Therefore, the choice of the plasma facing materials (PFMs) is a fundamental aspect in the design of these components. Tungsten is presently the main candidate being characterised by several advantages from a thermo-physical point of view, but also some drawbacks (e.g. significant activation under neutron irradiation). Neutronics assessment plays a key role in the design of these critical components and in the choice of the most suitable PFMs. Detailed nuclear analyses have been performed by implementing, for the first time, heterogeneous models of the actual ITER-Like PFCs geometry [1,2], aimed to assess the impact of neutronics and activation issues on design, lifetime, operations and safety of the PFCs of DEMO divertor and to provide outcomes useful in the PFCs selection concept, under study within the EUROfusion WPDIV-2 project. In particular way, the effects of two different blankets (WCLL and HCPB) on W activation and the impact of three different W compositions and chromium, have been compared. Three-dimensional neutronic analyses have been performed with the MCNP5 Monte Carlo [3] using the reference JEFF 3.3 nuclear data libraries [4] to calculate neutron spectra in PFCs subcomponents. Activation analysis has been performed with FISPACT II inventory codes [5] to assess the specific activity, decay heat and contact dose at the end of DEMO-1 operations. The calculations have been carried-out on ENEA HPC CRESCO6 cluster (Ponti et al., 2014).I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
