A5102734225- Magnetic confinement fusion research
- Superconducting Materials and Applications
- Fusion materials and technologies
- Particle accelerators and beam dynamics
- Ionosphere and magnetosphere dynamics
- Nuclear reactor physics and engineering
- Laser-Plasma Interactions and Diagnostics
- Advanced Data Storage Technologies
- Plasma Diagnostics and Applications
- Parallel Computing and Optimization Techniques
- Gyrotron and Vacuum Electronics Research
- Distributed and Parallel Computing Systems
- Nuclear Materials and Properties
- Atomic and Subatomic Physics Research
- High-Energy Particle Collisions Research
- Real-time simulation and control systems
- Corporate Governance and Law
- Legal and Labor Studies
- Model Reduction and Neural Networks
- Real-Time Systems Scheduling
- Petri Nets in System Modeling
- Fault Detection and Control Systems
- Fluid Dynamics and Turbulent Flows
- Magnetic Field Sensors Techniques
- Muon and positron interactions and applications
Fusion for Energy
2014-2024
Royal Military Academy
2020
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2013
Culham Science Centre
2003-2013
CEA Cadarache
2013
Princeton University
2012
United Kingdom Atomic Energy Authority
2003-2010
Culham Centre for Fusion Energy
2001-2010
Polytechnic University of Turin
2009
University of Cagliari
2009
The understanding and predictive capability of transport physics plasma confinement is reviewed from the perspective achieving reactor-scale burning plasmas in ITER tokamak, for both core edge regions. Very considerable progress has been made understanding, controlling predicting tokamak across a wide variety conditions regimes since publication Physics Basis (IPB) document (1999 Nucl. Fusion 39 2137–2664). Major areas considered here follow. (1) Substantial improvement content, reliability...
Analysis of Type I ELMs from ongoing experiments shows that ELM energy losses are correlated with the density and temperature pedestal plasma before crash. The loss normalized to is found correlate across collisionality (ν*ped), decreasing increasing ν*ped. Other parameters affect size, such as edge magnetic shear, etc, which influence volume affected by ELMs. particle influenced this weakly dependent on other parameters. In JET DIII-D, under some conditions, can be observed (`minimum'...
The scaling of the energy confinement in H mode plasmas with different hydrogenic isotopes (hydrogen, deuterium, DT and tritium) is investigated JET. For ELM-free modes thermal time τth found to decrease weakly isotope mass (τth ∼M-0.25±0.22), whilst ELMy shows practically no dependence ∼M0.03±0.1). Detailed local transport analysis reveals that edge region increases strongly mass, whereas core decreases (τthcore ∝ M-0.16), approximate agreement theoretical models gyro-Bohm type (τgB ∼M-0.2).
Development of real-time applications is usually associated with nonportable code targeted at specific operating systems. The boundary between hardware drivers, system services, and user commonly not well defined, making the development in target host significantly difficult. Multithreaded Application Real-Time executor (MARTe) a framework built over multiplatform library that allows execution same different provides high-level interfaces hardware, external configuration programs,...
Results are presented from a series of dedicated experiments carried out on JET in tritium, DT, deuterium and hydrogen plasmas to determine the dependence H mode power threshold plasma isotopic mass. The Pthr ∝ Aeff-1 scaling is established over whole range. This result makes it possible for fusion reactor with 50:50 DT mixture access regime about 20% less than that needed DD mixture. first systematic measurements necessary transition type I ELM regime, which occurs after mode, also...
Recent experiments on the Type I ELMy H-mode regime performed at JET with improved diagnostics have expanded range of parameters for study ELM energy and particle losses. Deviations from standard behaviour such losses in some areas operating space revealed that are correlated (density temperature) pedestal plasma before crash, while other global characteristics (such as frequency) a consequence ELM-driven flux in-between confinement. The relative loss (to energy) is found to correlate well...
Results are presented of experiments carried out in JET with the Mark II divertor to study ELMy H modes at high density. In these effective ion mass plasma (pure hydrogen, deuterium and tritium), input power, current edge triangularity were varied. The variation density was achieved by gas fuelling. focus is on two main issues: global energy confinement scaling mode pedestal. It found that dependence ITER97-P(y) not confirmed experiment when limit approached. For regime a independent...
New experimental results on transient loads during ELMs and disruptions in present divertor tokamaks are described used to carry out a extrapolation ITER reference conditions draw consequences for its operation. In particular, the achievement of low energy/convective type I edge localized modes (ELMs) ITER-like plasma seems only way obtain which may be compatible with an acceptable erosion lifetime facing components (PFCs) ITER. Power disruptions, contrary, seem lead most cases because...
We present the results of experiments in JET to study effect plasma shape on high density ELMy H-modes, with geometry magnetic boundary similar that envisaged for standard Q = 10 operation ITER. The described are single lower null plasmas, q profile, neutral beam heating and gas fuelling, average triangularity δ calculated at separatrix ~0.45-0.5 elongation κ~1.75. In agreement previous obtained other divertor Tokamaks, thermal energy confinement time maximum achievable steady state a given...
Operating experimental devices have provided key inputs to the design process for ITER axisymmetric control. In particular, experiments quantified controllability and robustness requirements in presence of realistic noise disturbance environments, which are difficult or impossible characterize with modelling simulation alone. This kind information is particularly critical vertical control, poses highest demands on poloidal field system performance, since consequences loss control can be...
Views Icon Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Twitter Facebook Reddit LinkedIn Tools Reprints and Permissions Cite Search Site Citation M. N. A. Beurskens, T. H. Osborne, P. Schneider, E. Wolfrum, L. Frassinetti, R. Groebner, Lomas, I. Nunes, S. Saarelma, Scannell, B. Snyder, D. Zarzoso, Balboa, Bray, Brix, J. Flanagan, C. Giroud, Giovannozzi, Kempenaars, Loarte, de la Luna, G. Maddison, F. Maggi, McDonald, Pasqualotto, Saibene, Sartori, Emilia...
This paper presents the experimental characterization of pedestal parameters, edge localized mode (ELM) energy, and particle losses from main plasma corresponding ELM energy fluxes on facing components for a series dedicated experiments in Joint European Torus (JET). From these experiments, it is demonstrated that simple hypothesis relating peeling-ballooning linear instability to not valid. Contrary previous observations at lower triangularities, small low collisionality have been obtained...
Several small/no ELM regimes such as EDA, grassy ELM, HRS, QH-mode, type II and V ELMs with good confinement properties have been obtained in Alcator C-Mod, ASDEX-Upgrade, DIII-D, JET, JFT-2M, JT-60U NSTX. All these show considerable reduction of instantaneous heat load onto divertor target plates contrast to conventional I energy losses are evaluated less than 5% the pedestal stored energy. These summarized widely categorized by their conditions terms operational space non-dimensional...
The main objective of this paper is investigation methods for reduction divertor heat loads in order to increase the lifetime tiles future fusion reactors.Special emphasis given studies transient due edge localized modes (ELMs).Two are compared: argon seeded type-I ELMy H-modes and nitrogen type-III H-modes.In both scenarios, impurity seeding leads a pedestal energy hence released by ELM.This consequentially reduces power load targets.At high radiative fractions H-modes, part that ELM (small...
Edge localized mode (ELM) measurements in many tokamaks, including ASDEX-Upgrade, DIII-D, JET, JT-60U and MAST, are reviewed, which includes progress experimental observations at the plasma edge region by means of fast-time resolved diagnostics with high precision, such as scanning probe, radial interferometer chord, BES tangentially viewing fast-gated camera midplane. ELM dynamics data show that majority particle energy transport should be dominated ion convection physics associated...
Real-time simultaneous control of several radially distributed magnetic and kinetic plasma parameters is being investigated on JET, in view developing integrated advanced tokamak scenarios. This paper describes the new model-based profile controller which has been implemented during 2006–2007 experimental campaigns. The aims to use combination heating current drive (H&CD) systems—and optionally poloidal field (PF) system—in an optimal way regulate evolution parameter profiles such as...
Self-consistent transport simulation of ITER scenarios is a very important tool for the exploration operational space and scenario optimisation. It also provides an assessment compatibility developed (which include fast transient events) with machine constraints, in particular poloidal field (PF) coil system, heating current drive (H&CD), fuelling particle energy exhaust systems. This paper discusses results predictive modelling all reference variants using two suite linked equilibrium...
Reactor relevant ICRH scenarios have been assessed during DT experiments on the JET tokamak using H mode divertor discharges with ITER-like shapes and safety factors. Deuterium minority heating in tritium plasmas was demonstrated for first time. For 9% deuterium, an power of 6 MW gave 1.66 fusion from reactions between suprathermal deuterons thermal tritons. The Q value steady state discharge reached 0.22 length RF flat-top (2.7 s), corresponding to three plasma energy replacement times....
An overview of JET experimental results in DT plasmas directly relevant to ITER modes operation is presented. Experiments D:T mixtures varying from 100:0 10:90 and those carried out hydrogen show that the H mode threshold power has an approximately inverse isotope mass dependence. Matching some key dimensionless parameters values, similarity experiments with shape safety factor q global energy confinement time practically independent isotopic (~A0.03±0.08), where A atomic hydrogenic species....
Ion cyclotron resonance heating (ICRH) experiments have been carried out in JET D-T plasmas using scenarios applicable to reactors. Deuterium minority tritium is used for the first time and produces 1.66 MW of fusion power an ICRH 6 MW. The $Q$ value 0.22, which a record steady state discharges. Fundamental $\mathrm{He}{}^{3}$ ICRH, both 50:50 dominated plasmas, generates strong bulk ion temperatures up 13 keV. Second harmonic seen heat mainly electrons as expected conditions. All three...
Recent progress in experimental and theoretical studies of edge localized mode (ELM) physics is reviewed for the reactor relevant plasma regimes, namely high confinement that is, H-modes advanced scenarios.
This paper describes experiments with highly shaped JET H-mode plasmas, which were directed to developing regimes where Type I ELMs are replaced by other edge relaxations, while maintaining the pedestal pressure of ELMy H-modes. It was found that II coexisted I, up densities order Greenwald limit, III appear, and good confinement lost. Only at highest collisionality it observed completely replace I. At high βp q95, 'grassy' completely. The MHD spectra characteristics for grassy significantly...
This paper presents the results of JET experiments aimed at studying operational space plasmas with a Type III ELMy edge, in terms both local and global plasma parameters. In JET, regime has wide pedestal ne – Te diagram, ELMs are observed standard H-modes as well an internal transport barrier (ITB). The transition from H-mode to steady state I requires minimum loss power, PTypeI. PTypeI decreases increasing triangularity. critical temperature for is found be inversely proportional density...
This paper describes some of the control problems faced by engineers working at Joint European Torus (JET), focusing mostly on plasma shape, position, and current. It details methodology used JET, which can serve as guide for design sophisticated multivariable, yet user friendly, controllers next generation fusion experiments.