About this Abstract |
Meeting |
2021 TMS Annual Meeting & Exhibition
|
Symposium
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Thermal Property Characterization, Modeling, and Theory in Extreme Environments
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Presentation Title |
Thermal Gradient Effect on the Transport Properties of Helium and Intrinsic Defects in Tungsten |
Author(s) |
Enrique Martinez Saez, Nithin Mathew, Danny Perez, Dimitrios Maroudas, Brian Wirth |
On-Site Speaker (Planned) |
Enrique Martinez Saez |
Abstract Scope |
Plasma-facing materials (PFMs) in a fusion reactor are expected to withstand high heat and particle fluxes. These fluxes will create strong gradients of temperature and concentration of diverse species. Intrinsic defects and He atoms will then migrate in the presence of such gradients. We have used nonequilibrium molecular dynamics to study the transport properties of He, and self-interstitials in the presence of a thermal gradient in tungsten. We observe that defects and impurity atoms tend to migrate toward the hot regions of the material. The resulting concentration profiles are in agreement with the predictions of irreversible thermodynamics. We compute a negative heat of transport, which indicates that the respective driven species fluxes are directed opposite to the heat flux. These results have important implications for PFMs in fusion environments, mostly when abnormal operation occurs in the plasma, which increases the heat flux towards the material and intensifies the thermal gradients. |
Proceedings Inclusion? |
Planned: |