A5001418286- Fusion materials and technologies
- Magnetic confinement fusion research
- Nuclear Materials and Properties
- Nuclear reactor physics and engineering
- Superconducting Materials and Applications
- Laser-Plasma Interactions and Diagnostics
- Nuclear Physics and Applications
- Ion-surface interactions and analysis
- Nuclear materials and radiation effects
- Metal and Thin Film Mechanics
- Metallurgical Processes and Thermodynamics
- Plasma Diagnostics and Applications
- Particle Dynamics in Fluid Flows
- Ionosphere and magnetosphere dynamics
- High-Energy Particle Collisions Research
- Advanced materials and composites
- Laser-induced spectroscopy and plasma
- High-pressure geophysics and materials
- High-Temperature Coating Behaviors
- Metallurgy and Material Forming
- Radiation Detection and Scintillator Technologies
- GaN-based semiconductor devices and materials
- Laser Material Processing Techniques
- Fluid Dynamics and Turbulent Flows
- X-ray Spectroscopy and Fluorescence Analysis
Culham Science Centre
2015-2024
Culham Centre for Fusion Energy
2015-2024
United Kingdom Atomic Energy Authority
2021-2024
Royal Military Academy
2020
Max Planck Society
2016
Max Planck Institute for Plasma Physics
2016
VTT Technical Research Centre of Finland
2013
KTH Royal Institute of Technology
2006-2013
Institute of Engineering Physics
2013
Moscow Engineering Physics Institute
2013
JET is used as a test bed for ITER, to investigate beryllium migration which connects the lifetime of first-wall components under erosion with tokamak safety, in relation long-term fuel retention. The (i) limiter and (ii) divertor configurations have been studied JET-ILW (JET Be first wall W divertor), compared those former JET-C carbon-based plasma-facing (PFCs)). For configuration, gross at contact point was determined situ by spectroscopy between 4% (Ein = 35 eV) more than 100%, caused...
Following the IAEA Technical Meeting on 'Advanced Methodologies for Analysis of Materials in Energy Applications Using Ion Beam Accelerators', this paper reviews current status ion beam analysis (IBA) techniques and some aspects ion-induced radiation damage materials field relevant to fusion. Available facilities, apparatus development, future research options challenges are presented discussed. The beryllium radioactivity-containing samples from experiments JET or ITER represents not only...
The erosion of tungsten (W), induced by the bombardment plasma and impurity particles, determines lifetime plasma-facing components as well impacting on performance influx W into confined region. screening divertor transport in largely content core, but source strength itself has a vital impact this process. JET tokamak experiment provides access to large set erosion-determining parameters permits detailed description closest ITER one: (i) effective sputtering yields fluxes function energy...
In October 2014, JET completed a scoping study involving high power scenario development in preparation for DT along with other experiments critical ITER.These have involved intentional and unintentional melt damage both to bulk beryllium main chamber tiles divertor tiles.This paper provides an overview of the findings concern machine protection ITER, illustrating each case resolution images taken by remote handling or after removal from machine.The upper dump plate some been repeatedly...
Following the first JET ITER-like wall operations a detailed in situ photographic survey of main chamber and divertor was completed. In addition, selection tiles passive diagnostics were removed from vessel made available for post mortem analysis. From results initial analysis, conclusions regarding erosion, deposition, fuel retention material transport during limiter phases have been drawn. The rate deposition on inner outer base remote corners more than an order magnitude less preceding...
Erosion and deposition were studied in the JET divertor during first ITER-like wall campaign 2011 to 2012 using marker tiles. An almost complete poloidal section consisting of tiles 0, 1, 3, 4, 6, 7, 8 was studied. The data from tile surfaces completed by analysis samples remote areas inner cladding. total mass material deposited decreased a factor 4–9 compared carbon all-carbon operation before 2010. Deposits consist mainly beryllium with 5–20 at.% oxygen, respectively, small amounts Ni,...
The First Mirror Test in Joint European Torus (JET) with the International Thermonuclear Experimental Reactor-like wall was performed polycrystalline molybdenum mirrors. Two major types of experiments were done. Using a reciprocating probe system main chamber, short-term exposure made during 0.3 h plasma operation 71 discharges. impact on reflectivity negligible. In long-term experiment lasting 19 13 X-point plasma, 20 Mo mirrors exposed, including four coated 1 μm-thick Rh layer. Optical...
Post-mortem studies with ion beam analysis, thermal desorption, and secondary mass spectrometry have been applied for investigating the long-term fuel retention in JET ITER-like wall components. The takes place via implantation co-deposition, highest values were found to correlate thickness of deposited impurity layers. From total amount retained D over half was detected divertor region. majority is on top surface inner divertor, whereas least measured main chamber mid-plane limiter....
Data on erosion and melting of beryllium upper limiter tiles, so-called dump plates (DP), are presented for all three campaigns in the JET tokamak with ITER-like wall. High-resolution images wall show clear signs flash ridge roof-shaped tiles. The melt layers move poloidal direction from inboard to outboard tile, ending last DP tile an upward going waterfall-like structure. Melting was caused mainly by unmitigated plasma disruptions. During ILW campaigns, around 15% 12376 pulses were...
ITER will use beryllium as a plasma-facing material in the main chamber, covering total surface area of about 620 m2. Given importance erosion and co-deposition for tritium retention ITER, significant efforts have been made to understand behaviour under fusion-relevant conditions with high particle heat loads. This paper provides comprehensive report on state knowledge conditions: mechanisms their consequences, migration JET, fuel dust generation. The reviews basic laboratory studies,...
Abstract After the second Deuterium–Tritium Campaign (DTE2) in JET tokamak with ITER-Like Wall (ILW) and full tritium campaigns that preceded followed after DTE2, a sequence of fuel recovery methods was applied to promote removal from wall components. The started several days baking main chamber walls at 240 °C 320 °C. Subsequently, superimposed Ion-Cyclotron Conditioning (ICWC) Glow Discharge (GDC) cleaning cycles deuterium. Diverted plasma operation deuterium different strike point...
Abstract The paper reports the first demonstration of in situ laser-induced desorption — quadrupole mass spectrometry (LID-QMS) application on a large scale fusion device performed summer 2023. LID-QMS allows direct measurements fuel inventory plasma facing components without retrieving them from device. diagnostic desorbs retained gases by heating 3 mm diameter spot wall using 1 ms long laser pulse and detects QMS. Thus, it can measure gas content at any position accessible to laser....
The evaluation of hydrogenic retention in present tokamaks is crucial importance to estimate the expected tritium (T) vessel inventory ITER, limited from safety considerations 350 g. In framework European Task Force on Plasma Wall Interaction (EU TF PWI) efforts are underway investigate gas balance and fuel during discharges, compare data obtained with those post-mortem analysis in-vessel components exposed over whole experimental campaigns. This paper summarizes principal findings...
Mechanisms underlying the retention of fuel species in tokamaks with carbon plasma-facing components are presented, together estimates for corresponding tritium ITER. The consequential requirement new and improved schemes to reduce inventory is highlighted results ongoing studies into a range techniques removal rate ITER each case. Finally, an approach involving integration many operational schedule proposed as means extend period operations before major intervention required.
In JET, lower hybrid (LH) and ion cyclotron resonance frequency (ICRF) wave absorption in the scrape-off layer can lead to enhanced heat fluxes on some plasma facing components (PFCs). Experiments have been carried out characterize these loads order to: (i) prepare JET operation with Be wall which has a reduced power handling capability as compared carbon (ii) better understand physics driving phenomena propose solutions for next generation systems reduce them. When using ICRF, hot spots are...
Post mortem analyses of JET ITER-Like-Wall tiles and passive diagnostics have been completed after each the first two campaigns (ILW-1 ILW-2). They show that global fuel inventory is still dominated by co-deposition; hence plasma parameters sputtering processes affecting material migration influence distribution retained fuel. In particular, differences between results from may be attributed to a greater proportion pulses run with strike points in divertor corners, having about 300...
Abstract Results of the first dust survey in JET with ITER-Like Wall (JET-ILW) are presented. The sampling was performed using adhesive stickers from divertor tiles where greatest material deposition detected after JET-ILW campaign 2011 – 2012. emphasis especially on and analysis metal particles (Be W) aim to determine composition, size, surface topography internal structure a large set methods: high-resolution scanning transmission electron microscopy, focused ion beam, diffraction also...
The work presented draws on new analysis of components removed following the second JET ITER-like wall campaign 2013–14 concentrating upper inner divertor, and outer divertor corners, lifetime issues relating to tungsten coatings carbon fibre composite tiles dust/particulate generation. results show that remains region highest deposition in JET-ILW. Variations plasma configurations between first have altered material migration corners divertor. Net is shown be beneficial sense it reduces W...
The recently developed Monte-Carlo code ERO2.0 is applied to the modelling of limited and diverted discharges at JET with ITER-like wall (ILW). global beryllium (Be) erosion deposition simulated compared experimental results from passive spectroscopy. For limiter configuration, it demonstrated that Be self-sputtering an important contributor (at least 35%) erosion. Taking this contribution into account, confirms previous evidence high deuterium (D) surface concentrations up ∼ 50% atomic...
Mirrors will be used as first plasma-viewing elements in optical and laser-based diagnostics ITER. Deterioration of the mirror performance due to e.g. sputtering surface by plasma particles or deposition impurities hamper entire affected diagnostic thus affect ITER operation. The Specialists Working Group on First (FM SWG) Topical Diagnostics International Tokamak Physics Activity (ITPA) plays an important role finding solutions for mirrors.
Abstract This paper reports the first experiment carried out in deuterium–tritium addressing integration of a radiative divertor for heat-load control with good confinement. Neon seeding was time D–T plasma as part second campaign JET its Be/W wall environment. The technical difficulties linked to re-ionisation heat load are reported T and D–T. compares impact neon on plasmas their D counterpart detachment, localisation radiation, scrape-off profiles, pedestal structure, edge localised modes global