A5066090149- Fusion materials and technologies
- Magnetic confinement fusion research
- Nuclear Materials and Properties
- Metal and Thin Film Mechanics
- Plasma Diagnostics and Applications
- Ion-surface interactions and analysis
- Nuclear reactor physics and engineering
- Laser-Plasma Interactions and Diagnostics
- Superconducting Materials and Applications
- Nuclear Physics and Applications
- Metallurgical Processes and Thermodynamics
- Ionosphere and magnetosphere dynamics
- High-Energy Particle Collisions Research
- High-pressure geophysics and materials
- Advanced materials and composites
- Advanced Data Storage Technologies
- Quantum, superfluid, helium dynamics
- Magnetic Properties and Applications
- Aeolian processes and effects
- Non-Destructive Testing Techniques
- Soil erosion and sediment transport
- Cold Fusion and Nuclear Reactions
- Particle physics theoretical and experimental studies
- Combustion and Detonation Processes
- Distributed and Parallel Computing Systems
University of Tennessee at Knoxville
2019-2024
Oak Ridge National Laboratory
2016-2020
Royal Military Academy
2020
University of Helsinki
2011-2017
Helsinki Institute of Physics
2017
Tekes
2013-2014
The provision of a particle and power exhaust solution which is compatible with first-wall components edge-plasma conditions key area present-day fusion research mandatory for successful operation ITER DEMO. work package plasma-facing (WP PFC) within the European programme complements laboratory experiments, i.e. in linear plasma devices, electron ion beam loading facilities, studies performed toroidally confined magnetic such as JET, ASDEX Upgrade, WEST etc. connection both groups done via...
We develop a multi-scale computational model for studying tungsten fuzz formation under low-energy He irradiation. The molecular dynamics and kinetic Monte Carlo results show that the W growth mechanism is following: atoms are trapped in W, forming bubbles causing by loop punching. close to surface rupture. balance between these processes leads stochastic growth, roughness thickness scale as . rates agree with experimental results.
The interaction of fusion reactor plasma with the material first wall involves a complex multitude interlinked physical and chemical effects. Hence, modern theoretical treatment it relies to large extent on multiscale modelling, i.e. using different kinds simulation approaches suitable for length time scales in connection each other. In this review article, we overview briefly physics chemistry plasma–wall interactions tokamak-like reactors, present some most commonly used relevant topic. We...
Linear plasma generators are cost effective facilities to simulate divertor conditions of present and future fusion reactors. They used address important R&D gaps in the science material interactions towards viable facing components for Next generation have be able access expected on targets ITER devices. The steady-state linear device MPEX will this regime with electron temperatures 1–10 eV densities . resulting heat fluxes about 10 MW is designed deliver those a novel Radio Frequency...
ERO is a Monte-Carlo code for modeling plasma-wall interaction and 3D plasma impurity transport applications in fusion research. The has undergone significant upgrade (ERO2.0) which allows increasing the simulation volume order to cover entire edge of device, allowing more self-consistent treatment comparison with larger number variety experimental diagnostics. In this contribution, physics-relevant technical innovations new version are described discussed. capabilities demonstrated by...
Abstract Integrated modeling of plasma-surface interactions provides a comprehensive and self-consistent description the system, moving field closer to developing predictive design capabilities for plasma facing components. One such workflow, including descriptions scrape-off-layer plasma, ion-surface sub-surface evolution, was previously used address steady-state scenarios has recently been extended incorporate time-dependence two-way information flow. The new model can dynamic recycling in...
Abstract A major challenge facing the design and operation of next-step high-power steady-state fusion devices is to develop a viable divertor solution with order-of-magnitude increases in power handling capability relative present experience, while having acceptable target plate erosion being compatible maintaining good core plasma confinement. new initiative has been launched on DIII-D scientific basis for design, installation, an advanced evaluate boundary solutions applicable next step...
Physical and chemical assisted physical sputtering were characterised by the Be I II line BeD band emission in observation chord measuring sightline integrated front of inner beryllium limiter at torus midplane. The 3D local transport plasma-surface interaction Monte-Carlo modelling (ERO code [18]) is a key for interpretation observations vicinity shaped solid limiter. plasma parameter variation (density scan) regime has provided useful material simulation benchmark. improved background...
Radio-frequency (RF)-enhanced surface erosion of beryllium (Be) plasma-facing components is explored, for the first time, using ERO code. The code applied to measured, RF-enhanced edge Be line emission at JET outboard limiters, in presence high-power, ion cyclotron-resonance heating (ICRH) L-mode discharges. In this modelling study, RF sheath effect from an ICRH antenna on a magnetically connected, limiter region simulated by adding constant potential local sheath, attempt match measured...
In this manuscript we introduce a simulation tool-suite for predicting plasma-surface interactions (PSI), which aims to predict the evolution of plasma-facing surfaces that continually change due exposure fusion plasmas. A comprehensive description PSI involves wide range physical phenomena, include components (a) gas implantation and its dynamic below divertor surface; (b) erosion wall material; (c) transport re-deposition eroded impurities; (d) scrape-off layer plasma including fuel ions...
For simulation of plasma-facing component erosion in fusion experiments, an analytical expression for the ion velocity just before surface impact including local electric field and optional biasing effect is suggested. Energy angular distributions resulting effective sputtering yields were produced several experimental scenarios at JET ILW mostly involving PFCs exposed to oblique magnetic field. The analytic solution has been applied as improvement earlier ERO modelling localized, Be outer...
We report the first detailed experimental verification of polar deuterium ion impact angle distribution (IAD) on DIII-D divertor surface in L-mode plasmas using micro-engineered trenches samples mounted DiMES probe. These were fabricated via focused beam (FIB) milling a silicon partially coated with aluminum. The sample surfaces exposed to eight repeat discharges (30 s total exposure time). examined by scanning electron microscopy (SEM), which revealed changes trench floor due material...
Abstract All plasma facing surfaces in a fusion reactor, whether initially pure or an alloy, will rapidly evolve into mixed material due to plasma-induced erosion, migration and redeposition. Beryllium (Be) erosion from the main chamber, its transport deposition on tungsten (W) divertor results growth of Be-W layers, which can form beryllides. These materials exhibit generally less desirable properties than beryllium, such as lower melting points. In order better understand parameter space...
Tungsten (W) and beryllium (Be) have been chosen as plasma-facing materials for the ITER reactor main fuel component will be deuterium (D). Due to plasma–wall interactions, these immediately mix via erosion, transport re-deposition. We present first atomistic study on effect of D co-implanted with Be into W, by modelling plus irradiation W surfaces, at projectile energies compositions relevant interactions. The implantation sticking yields increased fraction in system, especially lowest...
We present an atomistic study on the D irradiation W–Be mixtures, including a comparison between molecular dynamics (MD) and binary collision approximation methods. compared reflection Be erosion yields after non-cumulative impacts, concluding that both methods agree qualitatively, but low-energy related chemical effects can be recognized in MD. also followed evolution of mixtures under cumulative irradiation. At low energies, surface deuterates, quickly saturating suppressing erosion.
In the recent ITER-Like Wall experiment at JET, tungsten (W) and beryllium (Be) are used as first wall plasma-facing materials. Due to plasma–wall interactions, these materials will erode, be transported, re-deposit mix. We present computational, atomistic, systematic study on W–Be material mixing under fusion-relevant conditions. To this end, W surfaces were irradiated by Be, varying impacting energy angle, followed annealing mixed layers. At low energies, a Be layer is deposited W,...
Experiments at JET showed locally enhanced, asymmetric beryllium (Be) erosion outer wall limiters when magnetically connected ICRH antennas were in operation. A first modeling effort using the 3D and scrape-off layer impurity transport code ERO reproduced qualitatively experimental outcome. However, local plasma parameters—in particular distributions are of interest—can be difficult to determine from available diagnostics so / input relies on output other codes simplified models, increasing...