Numerical simulations on gaseous flow and heat transfer in multiple narrow channels of IFMIF High Flux Test Module

The International Fusion Materials Irradiation Facility (IFMIF) is designated to generate a materials irradiation database for the future fusion reactors. In the High Flux Test Module (HFTM) the test specimens will undergo a severe structural damage caused by neutron fluxes. The HFTM will be with helium gas. This paper presents the comprehensive thermo-hydraulic simulations of the HFTM as a part of the design activities. The turbulence models were assessed by comparing the simulations with in-house annular channel experiments. Since the required coolant flow rates are different for different compartments, multiple fluid domains were employed and simulated with appropriate turbulence (laminar) models individually. The flow distributions and heat transfer characteristics among various HFTM sub-channels will be discussed. Sensitivity study was carried out to assess the impacts of several factors on the simulation results.