A5041325926- Magnetic confinement fusion research
- Fusion materials and technologies
- Ionosphere and magnetosphere dynamics
- Superconducting Materials and Applications
- Laser-Plasma Interactions and Diagnostics
- Particle accelerators and beam dynamics
- Plasma Diagnostics and Applications
- Nuclear reactor physics and engineering
- Solar and Space Plasma Dynamics
- Mineral Processing and Grinding
- Minerals Flotation and Separation Techniques
- Nuclear Materials and Properties
- Astro and Planetary Science
- Planetary Science and Exploration
- Nuclear Physics and Applications
- Soil Mechanics and Vehicle Dynamics
- Advanced Control Systems Optimization
- Plasma and Flow Control in Aerodynamics
- Image and Signal Denoising Methods
- Radiation Effects in Electronics
- Utopian, Dystopian, and Speculative Fiction
- Vacuum and Plasma Arcs
- Advanced Control Systems Design
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- Writing and Handwriting Education
Culham Centre for Fusion Energy
2013-2025
Culham Science Centre
2014-2024
United Kingdom Atomic Energy Authority
2020-2024
Durham University
2022
Royal Military Academy
2020
European Organization for Nuclear Research
2017
Japan External Trade Organization
2014
University of Liverpool
1997-2013
CEA Cadarache
2013
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2013
A multi-machine database for the H-mode scrape-off layer power fall-off length, λq in JET, DIII-D, ASDEX Upgrade, C-Mod, NSTX and MAST has been assembled under auspices of International Tokamak Physics Activity. Regression inside finds that most important scaling parameter is poloidal magnetic field (or equivalently plasma current), with decreasing linearly increasing Bpol. For conventional aspect ratio tokamaks, regression , yielding λq,ITER ≅ 1 mm baseline inductive burning scenario at Ip...
A newly established scaling of the ELM energy fluence using dedicated data sets from JET operation with CFC & ILW plasma facing components (PFCs), ASDEX Upgrade (AUG) both and full-W PFCs MAST walls has been generated. The reveals an approximately linear dependence peak pedestal top electron pressure minor radius; a square root is seen on relative loss energy. result this gives range in parallel 10–30 MJm−2 for ITER Q= 10 2.5–7.5 intermediate at 7.5 MA 2.65 T. These latter numbers are...
Divertor detachment is explored on the TCV tokamak in alternative magnetic geometries. Starting from typical single-null shapes, poloidal flux expansion at outer strikepoint varied by a factor of 10 to investigate X-divertor characteristics, and total 70 study properties super-X divertor. The effect an additional X-point near target investigated divertors. Detachment studied these plasmas during Ohmic density ramps with ion B drift away primary X-point. threshold, depth detachment, stability...
The interaction of static Resonant Magnetic Perturbations (RMPs) with the plasma flows is modeled in toroidal geometry, using non-linear resistive MHD code JOREK, which includes X-point and scrape-off-layer. Two-fluid diamagnetic effects, neoclassical poloidal friction a source rotation are introduced model to describe realistic flows. RMP penetration studied taking self-consistently into account effects these radial electric field evolution. JET-like, MAST, ITER parameters used modeling....
Disruption prediction and avoidance is a critical need for next-step tokamaks, such as ITER. Event Characterization Forecasting (DECAF) research fully automates analysis of tokamak data to determine chains events that lead disruptions forecast their evolution allowing sufficient time mitigation or complete the disruption. event related local rotating global magnetohydrodynamic (MHD) modes vertical instability are examined with warnings issued many off-normal physics events, including density...
Sustained edge-localized mode (ELM) mitigation has been achieved using resonant magnetic perturbations (RMPs) with a toroidal number of n = 4 and 6 in lower single null 3 connected double plasmas on MAST. The ELM frequency increases by up to factor eight similar reduction energy loss. A threshold current for is observed above which the approximately linearly coils. comparison filament structures during ELMs natural mitigated stages shows that have characteristics type I even though their...
A multi-device database of disruption characteristics has been developed under the auspices International Tokamak Physics Activity magneto-hydrodynamics topical group. The purpose this ITPA (IDDB) is to find commonalities between and mitigation in a wide variety tokamaks order elucidate physics underlying tokamak disruptions extrapolate toward much larger devices, such as ITER future burning plasma devices. In contrast previous smaller data collation efforts, IDDB aims provide significant...
We present the first analysis of atomic and molecular processes at play during detachment in MAST-U Super-X divertor using spectroscopy data. Our indicates can be separated into four sequential phases: First, ionisation region detaches from target onset leaving a increased densities downstream. The plasma interacts with these molecules, resulting ions ($D_2^+$ and/or $D_2^- \rightarrow D + D^-$) that further react leading to Molecular Activated Recombination Dissociation (MAR MAD), which...
Sustained edge localized mode (ELM) mitigation has been achieved on MAST and AUG using resonant magnetic perturbations (RMPs) with various toroidal numbers over a wide range of low to medium collisionality discharges. The ELM energy loss peak heat loads at the divertor targets have reduced. phase is typically associated drop in plasma density overall stored energy. In one particular scenario MAST, by carefully adjusting fuelling it possible counteract produce plasmas mitigated ELMs, reduced...
Abstract The integration of good core and edge/pedestal confinement with strong dissipation heat particles in the divertors is a significant challenge for development fusion energy. Alternative divertor configurations offer potential advantages by broadening operational space where device can operate detached acceptable power exhaust. First results from MAST Upgrade are presented high mode experiments outer Super-X configuration, showing that naturally detach when formed no discernible...
Abstract Determining stress and strain in a component of fusion power plant involves defining boundary conditions for the mechanical equilibrium equations, which implies availability full reactor model those conditions. To address this fundamental challenge design, finite element method (FEM) Mega-Ampere Spherical Tokamak Upgrade (MAST-U) tokamak, operating at Culham Campus UKAEA, has been developed applied to assess deformations, strain, tokamak structure, taken as proxy plant. The model,...
In this paper we present in situ satellite data, theory, and laboratory validation that show how small-scale collisionless shocks minimagnetospheres can form on the electron inertial scale length. The resulting retardation deflection of solar wind ions could be responsible for unusual ``lunar swirl'' patterns seen surface Moon.
Major developments on the Mega Amp Spherical Tokamak (MAST) have enabled important advances in support of ITER and physics basis a spherical tokamak (ST) based component test facility (CTF), as well providing new insight into underlying physics. For example, L–H transition studies benefit from high spatial temporal resolution measurements pedestal profile evolution (temperature, density radial electric field) stability edge current has been inferred motional Stark effect measurements. The...
The distortion of the plasma boundary when three-dimensional resonant magnetic perturbations (RMPs) are applied has been measured in MAST H-mode plasmas. When n = 3 RMPs to control edge-localized modes (ELMs), experiences a strong toroidal corrugation. displacement is at various locations and found be order 5% minor radius for an field magnitude which mitigates ELMs. empirically observed corrugation edge position agrees well with ideal equilibrium reconstruction.
SOLPS simulations of MAST-U have been carried out to identify in more detail the physics and operational properties novel divertor configurations such as Super-x (SXD), particular detachment. A well diagnosed L-mode discharge from MAST has utilised determine transport coefficients representative for plasmas. Simulations show that under same core plasma conditions, SXD is strongly detached whilst conventional (CD) not (1 eV versus 20 at plate). The detachment higher power losses (1.6×)...
Abstract This contribution aims to improve existing scalings of the L-mode power decay length <?CDATA ${\lambda_{q}^{{\rm omp}}}$?> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:msubsup> <mml:mi>λ</mml:mi> <mml:mi>q</mml:mi> </mml:mrow> <mml:mi mathvariant="normal">o</mml:mi> mathvariant="normal">m</mml:mi> mathvariant="normal">p</mml:mi> </mml:msubsup> </mml:math> , especially for plasma configurations with strike points at ITER-relevant...
A prototype infrared video bolometer (IRVB) was successfully deployed in the Mega Ampere Spherical Tokamak Upgrade (MAST or MAST-U), first deployment of such a diagnostic spherical tokamak. The IRVB designed to study radiation around lower x-point, another tokamaks, and has potential estimate emissivity profiles with spatial resolution beyond what is achievable resistive bolometry. system fully characterized prior installation on MAST-U, results are summarized here. After installation, it...
Abstract This paper shows first quantitative analysis of the detachment processes in MAST Upgrade Super-X divertor (SXD). We identify an unprecedented impact plasma-molecular interactions involving molecular ions (likely <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msubsup> <mml:mi>D</mml:mi> <mml:mn>2</mml:mn> <mml:mo>+</mml:mo> </mml:msubsup> </mml:math> ), resulting strong ion sinks (Molecular Activated Recombination—MAR), leading to a reduction target...
Edge localized modes (ELMs) are a concern for future devices, such as ITER, due to the large transient heat loads they generate on divertor surfaces which could limit operational lifetime of device. This paper discusses application resonant magnetic perturbations (RMPs) mechanism ELM control Mega Amp Spherical Tokamak (MAST). Experiments have been performed using an n = 3 toroidal mode number perturbation and measurements strike point splitting performed. The made both infrared visible...
Several improvements to the MAST plant and diagnostics have facilitated new studies advancing physics basis for ITER DEMO, as well future spherical tokamaks (STs). Using increased heating capabilities P NBI ⩽ 3.8 MW H-mode at I p = 1.2 MA was accessed showing that energy confinement on scales more weakly with strongly B t than in IPB98( y , 2) scaling. Measurements of fuel retention shallow pellets extrapolate an particle throughput 70% its original designed total capacity. The anomalous...
Optimal correction of the intrinsic, static error field (EF) by coils in MAST is numerically studied, based on linear, full MHD plasma response computed toroidal geometry. Various optimization criteria are proposed, and results compared with empirical optima from representative EF (EFC) experiments. The two best thus identified, one aiming at minimization net resonant electromagnetic torque produced column EF, other corresponds to cancellation 2/1 harmonic q = 2 surface, including response....
Recent development of the nonlinear magneto hydrodynamic (MHD) code JOREK has enabled alignment its two-dimensional finite-element grid along poloidal flux surfaces for double-null Grad–Shafranov equilibria. In previous works with code, only single X-point plasmas were studied. The fast-camera diagnostic on MAST, which gives a global view pedestal filamentation during an ELM crash, clearly shows filaments travelling far into scrape-off layer, as first wall. Simulation such filament dynamics...
The transport of particles via intermittent filamentary structures in the private flux region (PFR) plasmas MAST tokamak has been investigated using a fast framing camera recording visible light emission from volume lower divertor, as well Langmuir probes and IR thermography monitoring particle power fluxes to plasma-facing surfaces divertor. data suggest that, divertor volume, fluctuations above X-point are strongest scrape-off layer (SOL). Conversely, below X-point, it is found that these...
Abstract This work presents a detailed characterisation of the MAST Scrape Off Layer in L-mode. Scans line averaged density, plasma current and toroidal magnetic field were performed. A comprehensive integrated study SOL was allowed by use wide range diagnostics. In agreement with previous results, an increase density induced broadening midplane profile. not correlated divertor detachment, as confirmed systematic target ion flux decrease emission. Also, no clear correlation is found neutral...