S. Denizeau
A5065186180- Particle accelerators and beam dynamics
- Magnetic confinement fusion research
- Plasma Diagnostics and Applications
- Particle Accelerators and Free-Electron Lasers
- Fusion materials and technologies
- Magnetic Field Sensors Techniques
- Electrostatic Discharge in Electronics
- Superconducting Materials and Applications
- Electrical Contact Performance and Analysis
- Electromagnetic Launch and Propulsion Technology
- Lightning and Electromagnetic Phenomena
- Vacuum and Plasma Arcs
National Agency for New Technologies, Energy and Sustainable Economic Development
2018-2024
University of Padua
2019-2024
Abstract The negative-ion based neutral beam injector for heating and current drive of the ITER plasma (ITER HNB) is under development, at present focusing on optimization full-scale source in SPIDER test stand. production H − or D ions ion low work function surfaces obtained by caesium evaporation. This paper describes conditioning procedure corresponding performances during first operation with caesium. Technical solutions to overcome limitations stand are described. influence parameters...
Heating neutral beam (HNB) injectors, necessary to achieve burning conditions and control plasma instabilities in ITER, are characterized by such demanding parameters that a test facility (NBTF) dedicated their development optimization is being realized Padua (Italy) with direct contributions from the Italian government (through Consorzio RFX as host entity) ITER international organization (with kind domestic agencies of Europe, Japan India) technical scientific support various European...
The requirements of ITER neutral beam injectors (1 MeV, 40 A negative deuterium ion current for 1 h) have never been simultaneously attained; therefore, a dedicated Neutral Beam Test Facility (NBTF) was set up at Consorzio RFX (Padova, Italy). NBTF includes two experiments: SPIDER (Source the Production Ions Deuterium Extracted from Rf plasma), full-scale prototype source injectors, with 100 keV accelerator, to investigate and optimize properties source; MITICA, entire injector, devoted...
An overview of the recent operations and main results cesium injection in Source for Production Ions Deuterium Extracted from Rf plasma (SPIDER) negative ion source are described this contribution. In experiments without injection, all SPIDER plants were tested to verify basic expectations on operational parameters (e.g., electron cooling effectiveness magnetic filter field) determine its region. For beam properties, it was shown that current density varies across vertical direction....
In June 2018 the SPIDER device, which is full-size prototype of negative ion source and extractor for ITER Heating Neutral Beam has entered first operation phase at Test Facility (NBTF) in Padova, Italy. This paper describes present status experimental plans results obtained during campaign radio-frequency driven plasma source.
Abstract Three years of experiments on SPIDER allowed characterization the main features source plasma and negative ion beam, in original design configuration. For large dimensions chamber, extraction area, investigation single-beamlet currents uniformity had to be carried out extend knowledge gained smaller prototype sources. The configuration multiple RF drivers filter field topologies were found cause a peculiar behavior confinement drivers, creating left-right asymmetries which also...
The NBTF (Neutral Beam Test Facility) in Padova, Italy, is dedicated to testing and optimizing the Neutral Injector for ITER. A full-scale prototype known as MITICA currently being constructed at demonstrate all design parameters ITER, including stable beam operation 1MeV energy. To achieve high voltage holding of 1MV, a campaign planned 2023, which will utilize realistic mockups ion source accelerator. During this campaign, mockup be biased with an increasing potential up -1MV, discharge...
In multi-beamlet negative ion accelerators for neutral beam injectors, the transverse magnetic field necessary suppressing co-extracted electrons induces a deflection of beamlets that must be corrected. For design, particle-tracing simulation codes are used to compute trajectories and optical properties in acceleration stage. these codes, uniform boundary conditions normally assumed current density distribution at surface (called meniscus), where ions extracted from plasma form beamlets,...
During 2016, a joint experimental campaign was carried out by QST and Consorzio RFX on the Negative Ion Test Stand (NITS) at Naka Fusion Institute, Japan, with purpose of validating some design solutions adopted in MITICA, which is full-scale prototype ITER NBI, presently under construction RFX, Padova, Italy.The main to test novel technique, for suppressing beamlet criss-cross magnetic deflection. This new involving set permanent magnets embedded Extraction Grid, named Asymmetric Deflection...
Abstract The experimental fusion reactor ITER will feature two (or three) heating neutral beam injectors (NBI) capable of delivering 33(or 50) MW power into the plasma. A NBI consists a plasma source for production negative ions (extracted ion current up to 329 A/m 2 in H and 285 D) then accelerated 1 MeV one hour. is neutralized, residual are electrostatically removed before injection. beamline was designed divergence between 3 7 mrad. NBIs relies on RF-driven, Inductively-Coupled Plasmas...
SPIDER (Source for the Production of Ions Deuterium Extracted from Rf plasma) is a full-scale prototype ITER NBI source. It based on concept inductive coupling between radio-frequency current drive and plasma. Present three-dimensional (3D) electromagnetic calculations stationary RF fields in permit an evaluation power dissipation its main constituents. Taking experimental plasma parameters as input, we concentrate copper-made Faraday shield lateral wall (FSLW) source discharges with without...
SPIDER is the prototype of ion source neutral beam injector (NBI) for ITER, and currently in operation at Neutral Beam Test Facility (NBTF), Consorzio RFX, Padova, Italy. The magnetic field important and, general, negative sources. It required filtering fast electrons plasma (magnetic filter field), thus enhancing production rate, suppressing coextracted accelerator (electron suppression field). In order to measure map SPIDER, a positioning system has been designed realized, then applied...
This work documents the initial 3D calculations to simulate coupling between radio-frequency (RF) waves and plasma in discharges of SPIDER device. Axisymmetric domain alone compare well against equivalent 2D cases. A model driver, cylindrical chamber where is heated by RF drive, then defined including metallic parts Faraday shield, insulator vacuum layer up winding (not included calculation domain). Estimates power share different are obtained using experimental conditions data. The results...
Two heating Neutral Beam Injectors (NBIs), required for plasma and current drive, are foreseen ITER operation. Each beam will be generated by a 40A of Deuterium negative ions, accelerated up to the specific energy 1MeV then neutralized, delivering power 16.5 MW each. The source (BS) constituted an RF-driven ion at –1 MV potential electrostatic accelerator (consisting 5 stages intermediate potentials). All components installed in vacuum vessel, together with high-capacity cryo-pumping system...