A5005277797- Magnetic confinement fusion research
- Fusion materials and technologies
- Superconducting Materials and Applications
- Ionosphere and magnetosphere dynamics
- Advanced Vision and Imaging
- Industrial Vision Systems and Defect Detection
- Laser-Plasma Interactions and Diagnostics
- Advanced Image and Video Retrieval Techniques
- CCD and CMOS Imaging Sensors
- Atomic and Molecular Physics
- Nuclear reactor physics and engineering
- Plasma Diagnostics and Applications
- Image and Object Detection Techniques
- Robotics and Sensor-Based Localization
- Image Processing Techniques and Applications
- Particle accelerators and beam dynamics
- Digital Image Processing Techniques
- Laser-induced spectroscopy and plasma
- Robotic Path Planning Algorithms
- Injection Molding Process and Properties
- Ship Hydrodynamics and Maneuverability
- Fluid Dynamics and Thin Films
- Material Properties and Processing
- Magnetic properties of thin films
- Financial Risk and Volatility Modeling
University of York
2017-2025
Culham Centre for Fusion Energy
2019-2024
United Kingdom Atomic Energy Authority
2024
Culham Science Centre
2019-2024
Royal Military Academy
2020
Northrop Grumman (United States)
2009
Integra (United States)
2009
Carnegie Mellon University
1991
Abstract The tokamak à configuration variable (TCV) continues to leverage its unique shaping capabilities, flexible heating systems and modern control system address critical issues in preparation for ITER a fusion power plant. For the 2019–20 campaign configurational flexibility has been enhanced with installation of removable divertor gas baffles, diagnostic capabilities an extensive set upgrades new dual frequency gyrotrons. baffles reduce coupling between main chamber allow detailed...
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...
Abstract The research program of the TCV tokamak ranges from conventional to advanced-tokamak scenarios and alternative divertor configurations, exploratory plasmas driven by theoretical insight, exploiting device’s unique shaping capabilities. Disruption avoidance real-time locked mode prevention or unlocking with electron-cyclotron resonance heating (ECRH) was thoroughly documented, using magnetic radiation triggers. Runaway generation high- Z noble-gas injection runaway dissipation...
Within the EUROfusion MST1 work package, a series of experiments has been conducted on AUG and TCV devices to disentangle role plasma fueling shape for onset small ELM regimes. On both devices, regimes with high confinement are achieved if only two conditions fulfilled at same time. Firstly, density separatrix must be large enough (), leading pressure profile flattening separatrix, which stabilizes type-I ELMs. Secondly, magnetic configuration close double null (DN), reduction shear in...
The mega amp spherical tokamak (MAST) was a low aspect ratio device (R/a = 0.85/0.65 ~ 1.3) with similar poloidal cross-section to other medium-size tokamaks. physics programme concentrates on addressing key issues for the operation of ITER, design DEMO and future tokamaks by utilising high resolution diagnostic measurements closely coupled theory modelling significantly advance our understanding. An empirical scaling energy confinement time that favours higher power, lower collisionality...
This paper shows experimental results from the TCV tokamak that indicate plasma-molecule interactions involving $D_2^+$ and possibly $D^-$ play an important role as sinks of energy (through hydrogenic radiation well dissociation) particles during divertor detachment if low target temperatures ($< 3$ eV) are achieved. Both molecular activated recombination (MAR) ion source reduction due to a power limitation effect shown be in reducing flux density ramp. In contrast, electron-ion (EIR) sink...
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 Detachment, an important mechanism for reducing target heat deposition, is achieved through reductions in power, particle and momentum; which are induced plasma–atom plasma–molecule interactions. Experimental research how those reactions precisely contribute to detachment limited. Both as well interactions can result excited hydrogen atoms emit atomic line emission. In this work, we investigate a new Balmer Spectroscopy technique Plasma–Molecule Interaction—BaSPMI. This first...
In this work we provide experimental insights into the impact of plasma–molecule interactions on target ion flux decrease during divertor detachment achieved through a core density ramp in TCV tokamak. Our improved analysis hydrogen Balmer series shows that processes are strongly contributing to intensities and substantially alter particle balance. We find Molecular Activated Recombination (MAR) sinks from H2+ (and possibly H−) factor ∼5 larger than Electron–Ion (EIR) significant contributor...
Abstract This work presents the use of a collisional-radiative model to infer plasma parameters from 2D emissivities several deuterium Balmer lines. The were obtained by MANTIS, an absolutely calibrated, ten-camera imaging polychromator with <?CDATA $< 5\,\mathrm{m}\mathrm{m}$?> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" overflow="scroll"> <mml:mo><</mml:mo> <mml:mn>5</mml:mn> <mml:mspace width="0.17em" /> <mml:mi mathvariant="normal">m</mml:mi> </mml:math>...
Abstract Within the 9th European Framework programme, since 2021 EUROfusion is operating five tokamaks under auspices of a single Task Force called ‘Tokamak Exploitation’. The goal to benefit from complementary capabilities each machine in coordinated way and help developing scientific output scalable future largre machines. programme this ensures that ASDEX Upgrade, MAST-U, TCV, WEST JET (since 2022) work together achieve objectives Missions 1 2 Roadmap: i) demonstrate plasma scenarios...
Ray-tracing techniques are applied to filtered divertor imaging, a diagnostic that has long suffered from artifacts due the polluting effect of reflected light in metal walled fusion machines. Physically realistic surface reflections were modeled using Cook-Torrance micro-facet bi-directional reflection distribution function high resolution mesh vessel geometry. In absence gonioreflectometer measurements, technique was developed fit free parameters model against images JET in-vessel sources....
The process of divertor detachment, whereby heat and particle fluxes to surfaces are strongly diminished, is required reduce loading erosion in a magnetic fusion reactor acceptable levels. In this paper the physics leading decrease total ion current (It), or 'roll-over', experimentally explored on TCV tokamak through characterization location, magnitude role various sinks sources including complete analysis power balance. These first measurements profiles ionisation hydrogenic radiation...
Abstract We present results of the design, implementation and testing a Bayesian multi-diagnostic inference system which combines various divertor diagnostics to infer 2D fields electron temperature T e , density n deuterium neutral 0 in divertor. The was tested using synthetic diagnostic measurements derived from SOLPS-ITER fluid code predictions MAST-U Super-X include appropriate added noise. Two simulations different states detachment, taken scan nitrogen seeding rate, were used as...
Purpose The purpose of this paper is to provide a practical review metal working fluids and their implications the machining practice. Despite widespread use applications, there are several scientific economic factors that call for an investigation current practices development new approaches. Design/methodology/approach There numerous methods diverge from traditional “wet” machining, which move towards environmentally friendly cost effective process. This includes looking at both minimum...
Abstract Recent results from MAST Upgrade are presented, emphasising understanding the capabilities of this new device and deepening key physics issues for operation ITER design future fusion power plants. The impact MHD instabilities on fast ion confinement have been studied, including first observation losses correlated with Compressional Global Alfvén Eigenmodes. High-performance plasma scenarios developed by tailoring early current ramp phase to avoid internal reconnection events,...
The pressure gradient of the high confinement pedestal region at edge tokamak plasmas rapidly collapses during plasma eruptions called localised modes (ELMs), and then re-builds over a longer time scale before next ELM. physics that controls evolution JET between ELMs is analysed for 1.4 MA, 1.7 T, low triangularity, δ = 0.2, discharges with ITER-like wall, finding typically tracks ideal magneto-hydrodynamic ballooning limit, consistent role kinetic mode. Furthermore, width often influenced...
Breeding blankets are designed to ensure tritium self-sufficiency in deuterium–tritium fusion power plants. In addition this, breeder play a vital role shielding key components of the reactor, and provide main source heat which will ultimately be used generate electricity. Blanket design is critical success reactors integral process. Neutronic simulations regularly performed ascertain performance particular design. An iterative process improvements parametric studies required optimize meet...
The physics of divertor detachment is determined by power, particle and momentum balance. This work provides a novel analysis technique the Balmer line series to obtain full particle/power balance measurement divertor. supplies new information understand what controls target ion flux during detachment. Atomic deuterium excitation emission separated from recombination quantitatively using ratios. enables analysing those two components individually, providing ionisation/recombination...
2D profiles of electron density and neutral temperature are inferred from multi-delay Coherence Imaging Spectroscopy data divertor plasmas using a non-linear inversion technique. The inference is based on imaging the spectral line-broadening Balmer lines can differentiate between Doppler Stark broadening components by measuring fringe contrast at multiple interferometric delays simultaneously. model has been applied to images generated simulated evaluate its performance. Typical mean...
Abstract A model for the pedestal density prediction based on neutral penetration combined with transport is presented. The tested against a database of JET-ILW Type I ELMy H-modes showing good agreement over wide range parameters both in standalone modelling (using experimental temperature profile) and full Europed that predicts pedestals simultaneously. further ASDEX Upgrade MAST-U are found to agree same as JET-ILW. experiment where isotope main ion varied D/T scan at constant gas rate...
Forestry has for many years been a major New Zealand industry, within which the manufacture of reconstituted products from wood fiber is becoming increasingly significant. The demand consistently high-quality surface finish in products, such as medium density fiberboard panels, introduces inspection requirements that cannot be easily met by manual inspection. This paper discusses development prototype system panels to detect and classify various defect types at production rates. range...