About this Abstract |
Meeting |
2016 TMS Annual Meeting & Exhibition
|
Symposium
|
Computational Methods for Spatio-temporal Scale-bridging: from Atomistics to Mesoscale
|
Presentation Title |
Scale-Bridging Modeling of Helium Segregation to Surfaces of Plasma-Exposed Tungsten |
Author(s) |
Sophie Blondel, Dimitrios Maroudas, Lin Hu, Karl D. Hammond, Brian D. Wirth |
On-Site Speaker (Planned) |
Sophie Blondel |
Abstract Scope |
We report a hierarchical multi-scale modeling study of implanted helium segregation to surfaces of tungsten, considered as a plasma facing component in nuclear fusion reactors. We employ a hierarchy of atomic-scale simulations based on a reliable interatomic interaction potential, including molecular-statics and molecular dynamics simulations to understand the origin of helium surface segregation. The near-surface cluster dynamics found in these simulations have significant effects on the surface morphology, near-surface defect structures, and the amount of helium retained in the material upon plasma exposure. We integrate the findings of such atomic-scale simulations into a properly parameterized and validated spatially-dependent, continuum-scale reaction-diffusion cluster dynamics model, capable of predicting implanted helium evolution, surface segregation, and its near-surface effects in tungsten. This cluster-dynamics model sets the stage for development of fully atomistically informed coarse-grained models for computationally efficient simulation predictions, toward optimal design of plasma facing components. |
Proceedings Inclusion? |
Planned: A print-only volume |