Modeling and Laboratory Experiments 1. Takuji Oda (the University of Tokyo, Japan) Multi-scale and multi-physics modeling of solid breeders 2. David Demange (KIT, Germany) Tritium coupled phenomena in solid breeder blanket concepts: state of the art rationale for future work plan 3. Yohji Seki (JAEA, Japan) Presented by Mikio Enoeda Experimental study of helium purge flow in pebble bed for solid breeder

Takuji Oda (the University of Tokyo, Japan) Multi-scale and multi-physics modeling of solid breeders Stability & diffusivity of tritium (including radiation effects) Pebble packing behavior by DEM Thermal mechanical modeling (FEM, DEM) Effects of radiation damage: atomic defects & crystallographic changes On thermal property, mechanical property, tritium behavior, etc Aging effects (long-term property robustness) Coupled phenomena/inter-scale/inter-physics phenomena Pebbles may be a good point that macro/micro can be integrated.

David Demange (KIT, Germany) Tritium coupled phenomena in solid breeder blanket concepts: state of the art rationale for future work plan Coupled phenomena; One to one correspondence of material parameters and operating conditions; Proposal for experiments in ITER TBM (repeating the same experiment, State of the art on simulations, consequences on tritium release and the necessity of the T measurements; Simulations with in-pile and out of pile expts.

Yohji Seki (JAEA, Japan) Presented by Mikio Enoeda Experimental study of helium purge flow in pebble bed for solid breeder Experimental study of pressure drop in the breeder pebble bed; Modelling with FLUENT Pressure drop in the breeder pebble bed and verification test of hydraulic performance of purge gas;

Summary Proper modelling (FEM, DEM) is required to capture the “Thermal mechanical” in single pebble and pebble bed The radiation damage which effects the thermal property, mechanical property, tritium behavior atomic defects & crystallographic changes etc. Propose a list of experiments/tests to be performed in ITER with the aim to achieve a reliable TBMs testing programme “satellites” experiments could be favoured when possible, recommended for fundamental aspects of coupled phenomena. Integrated simulation of heat and mass transfer in blanket Integrated simulation of heat and mass transfer (to estimate the generated tritium and its transport, to contribute to the design of blanket.