Integration of coupled modeling of the core and divertor plasmas into “FC-FNS” code and application to DEMO-FNS project

Abstract The “FC-FNS” (Fusion Cycle for Fusion Neutron Source) fuel cycle model is used to calculate the hydrogen isotope flows in the fuel systems of a tokamak-based fusion neutron source (FNS). The present development incorporates into the FNS model the coupled modeling of the core and divertor plasmas that provides the relation between the plasma parameters and particle fluxes through the vacuum chamber in steady state operation. The upgraded “FC-FNS” code is applied to the analysis of the DEMO-FNS project based on a tokamak with the parameters R/a = 3.2 m/1 m, B = 5 T, Ipl = 4–5 MА, PNBI =30 MW, PECR =6 MW and DT fusion power Pfus =40 MW. The possibility of reducing the hydrogen fluxes in the pumping and injection systems when using an admixture of Ne in a diverter is substantiated. The operation mode of the DEMO-FNS fueling systems depending on the main plasma parameters is analyzed and the gas flows for different D2/T2/DT pellet injection modes are evaluated.