Tritium Transport Evolutions in HCCR TBM Under ITER Inductive Operations

Abstract

First-of-a-kind numerical simulation was performed to evaluate time dependent tritium transport properties for Korea’s HCCR (Helium-Cooled Ceramic Reflector) TBM (Test Blanket Module) design under ITER inductive operating conditions. The estimation of tritium inventories in various components of the HCCR submodule and its permeation amount into the helium coolant was obtained through three computational models involving: 1) a 3D FW standalone model where diffusion and permeation into FW He coolant through tritium ion implantation was studied, 2) a 2D Poloidal-Radial (P-R) mid-plane model where the effect of increased tritium concentration in the purge gas stream was accounted for, and 3) a 2D Toroidal-Radial (T-R) mid-plane model to study tritium concentration accumulation in the He coolant. The analysis shows that tritium inventory in the breeder reaches an equilibrium value in about 10 cycles, and is about 0.373 mg per submodule. Tritium inventory in the ferritic steel structure reaches its equilibrium value in less than 10 cycles, and has about 0.0012 mg per submodule at the end of the plasma burn. The amount of the tritium permeated into helium coolant is about 1.8% of the amount of tritium produced per cycle.