A5049283308- Magnetic confinement fusion research
- Fusion materials and technologies
- Superconducting Materials and Applications
- Particle accelerators and beam dynamics
- Laser-Plasma Interactions and Diagnostics
- Plasma Diagnostics and Applications
- High-pressure geophysics and materials
- Nuclear Physics and Applications
- Thermal properties of materials
- Solar and Space Plasma Dynamics
- Ionosphere and magnetosphere dynamics
- Electromagnetic Scattering and Analysis
- Astronomy and Astrophysical Research
- Nuclear reactor physics and engineering
- Gyrotron and Vacuum Electronics Research
- Gas Dynamics and Kinetic Theory
- Electromagnetic Compatibility and Measurements
- Microwave and Dielectric Measurement Techniques
- Astronomical Observations and Instrumentation
- Atomic and Molecular Physics
Royal Military Academy
2023
Forschungszentrum Jülich
2011-2021
Abstract We present recent highlights from the most operation phases of Wendelstein 7-X, advanced stellarator in world. Stable detachment with good particle exhaust, low impurity content, and energy confinement times exceeding 100 ms, have been maintained for tens seconds. Pellet fueling allows plasma reduced ion-temperature-gradient turbulence, during such phases, overall is so (energy often 200 ms) that attained density temperature profiles would not possible less optimized devices, since...
Abstract After a long device enhancement phase, scientific operation resumed in 2022. The main new components are the water cooling of all plasma facing and water-cooled high heat flux divertor units. Water allowed for first long-pulse campaign. A maximum discharge length 8 min was achieved with total heating energy 1.3 GJ. Safe demonstrated attached detached mode. Stable detachment is readily some magnetic configurations but requires impurity seeding small pitch angle within edge islands....
Optical lifetime of the first mirror is a critical issue for ITER upper-port-plug core-charge-exchange-spectroscopy diagnostic. A fast shutter engaged to protect from depositions between measurements. The prototype will be examined in test vacuum vessel that now under development Forschungszentrum Jülich, Germany. Being located near plasma, operates severe thermal and electromagnetic (EM) loads. multifield analyses conducted are presented this paper. Since can operate within 0.7 s, its...
In optical diagnostic systems of ITER, mirrors will be used to guide the light from plasma towards detectors and cameras. The subjected erosion due fast particles deposition impurities which affect adversely mirror reflectivity therefore must suppressed or mitigated at maximum possible extent. Predictive modeling envisages successful suppression in ducts with fins trapping on their way located end these ducts. To validate predictions, cylindrical cone-shaped were exposed TEXTOR for 3960 s...
The newly developed ICRH antenna system for the stellarator W7-X will be available Operational Phase 2.1. design and application of various components in was validated using a prototype box with straps. Electromagnetic characteristics were measured optimized while reconsidering thermal mechanical aspects. As result, several improved introduced to final design. layout new matching allows operation at 25 MHz 37.5 without use additional line stretchers. refurbished two radio frequency (RF)...
An important test for W7-X is to demonstrate confinement of fast trapped ions at volume averaged beta values up 5%, corresponding plasma densities above 1020 m−3. Energetic in with energies 50 < E 100 keV mimic alphas a reactor. To generate such population challenging task high-density plasmas but this can be efficiently realized the H- (3He)-D three-ion heating ICRH scenario, foreseen f∼25 MHz W7-X. system prepared W7-X, expected deposit RF powers ∼1.5 MW (depending on coupling) frequencies...
Optical lifetime of the first mirror is a critical issue for ITER upper port plug core charge exchange spectroscopy diagnostic (cCXRS). A fast shutter engaged to protect from depositions between measurements. The prototype will be examined in test vacuum vessel that now under development Forschungszentrum Jülich, Germany. Being located near plasma, operates severe thermal and electromagnetic (EM) loads. multi-field analyses conducted are presented paper. Since can operate within 1 second,...
The research on plasma facing components in view of wall interactions is advancing towards a new level with the availability long pulse machines. With Wendelstein 7-X (W7-X) first stellarator provides steady-state discharges up to 30 min next operation phase (OP2). To support investigation PWI processes fast sample and component exchange, divertor manipulator accompanying observation system laser injection development. introduction probe heads into W7-X proceeds roughly along developed use...