1
|
Micheletti P, Baquero-Ruiz M, Manke F, Furno I, Ricci P, Fasoli A, Bowen P, Morais C, Zhao W. Cathodoluminescent screen imaging system for seeded blob detection in toroidal plasma experiment. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2020; 91:053501. [PMID: 32486748 DOI: 10.1063/1.5123038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Accepted: 04/15/2020] [Indexed: 06/11/2023]
Abstract
We designed and built a diagnostic based on a cathodoluminescent screen for the detection of turbulent plasma structures with high spatial resolution. The screen is coated with a low threshold energy cathodoluminescent powder that emits light when exposed to a plasma. The emitted light is imaged with a fast frame camera combined with an image intensifier and an optical bandpass filter. The diagnostic is used to study turbulent structures and seeded blobs. The results are analyzed with pattern recognition algorithms to track the turbulent structures and study their evolution in time.
Collapse
Affiliation(s)
- P Micheletti
- École Polytechnique Fédérale de Lausanne (EPFL), Swiss Plasma Center (SPC), CH-1015 Lausanne, Switzerland
| | - M Baquero-Ruiz
- École Polytechnique Fédérale de Lausanne (EPFL), Swiss Plasma Center (SPC), CH-1015 Lausanne, Switzerland
| | - F Manke
- École Polytechnique Fédérale de Lausanne (EPFL), Swiss Plasma Center (SPC), CH-1015 Lausanne, Switzerland
| | - I Furno
- École Polytechnique Fédérale de Lausanne (EPFL), Swiss Plasma Center (SPC), CH-1015 Lausanne, Switzerland
| | - P Ricci
- École Polytechnique Fédérale de Lausanne (EPFL), Swiss Plasma Center (SPC), CH-1015 Lausanne, Switzerland
| | - A Fasoli
- École Polytechnique Fédérale de Lausanne (EPFL), Swiss Plasma Center (SPC), CH-1015 Lausanne, Switzerland
| | - P Bowen
- École Polytechnique Fédérale de Lausanne (EPFL), Powder Technology Laboratory (LTP), CH-1015 Lausanne, Switzerland
| | - C Morais
- École Polytechnique Fédérale de Lausanne (EPFL), Powder Technology Laboratory (LTP), CH-1015 Lausanne, Switzerland
| | - W Zhao
- École Polytechnique Fédérale de Lausanne (EPFL), Powder Technology Laboratory (LTP), CH-1015 Lausanne, Switzerland
| |
Collapse
|
2
|
Chellaï O, Alberti S, Baquero-Ruiz M, Furno I, Goodman T, Manke F, Plyushchev G, Guidi L, Koehn A, Maj O, Poli E, Hizanidis K, Figini L, Ricci D. Millimeter-Wave Beam Scattering by Field-Aligned Blobs in Simple Magnetized Toroidal Plasmas. PHYSICAL REVIEW LETTERS 2018; 120:105001. [PMID: 29570337 DOI: 10.1103/physrevlett.120.105001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Indexed: 06/08/2023]
Abstract
The first direct experimental measurements of the scattering of a millimeter-wave beam by plasma blobs in a simple magnetized torus are reported. The wavelength of the beam is comparable to the characteristic size of the blob. In situ Langmuir probe measurements show that fluctuations of the electron density induce correlated fluctuations of the transmitted power. A first-principles full-wave model, using conditionally sampled 2D electron density profiles, predicts fluctuations of the millimeter-wave power that are in agreement with experiments.
Collapse
Affiliation(s)
- O Chellaï
- Swiss Plasma Center (SPC), École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - S Alberti
- Swiss Plasma Center (SPC), École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - M Baquero-Ruiz
- Swiss Plasma Center (SPC), École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - I Furno
- Swiss Plasma Center (SPC), École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - T Goodman
- Swiss Plasma Center (SPC), École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - F Manke
- Swiss Plasma Center (SPC), École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - G Plyushchev
- Swiss Plasma Center (SPC), École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - L Guidi
- Max Planck Institute for Plasma Physics, 85748 Garching, Germany
| | - A Koehn
- Max Planck Institute for Plasma Physics, 85748 Garching, Germany
- Institute of Interfacial Process Engineering and Plasma Technology, University of Stuttgart, 70174 Stuttgart, Germany
| | - O Maj
- Max Planck Institute for Plasma Physics, 85748 Garching, Germany
| | - E Poli
- Max Planck Institute for Plasma Physics, 85748 Garching, Germany
| | - K Hizanidis
- National Technical University of Athens, 106 82 Athens, Greece
| | - L Figini
- Istituto di Fisica del Plasma, Consiglio Nazionale delle Ricerche, 20125 Milan, Italy
| | - D Ricci
- Istituto di Fisica del Plasma, Consiglio Nazionale delle Ricerche, 20125 Milan, Italy
| |
Collapse
|
3
|
Mikaili Agah K, Salar Elahi A, Ghoranneviss M. Biasing Effect on the Edge Plasma Electrical Fluctuations in IR-T1 Tokamak. JOURNAL OF FUSION ENERGY 2016. [DOI: 10.1007/s10894-016-0117-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
4
|
Angus JR, Umansky MV, Krasheninnikov SI. Effect of drift waves on plasma blob dynamics. PHYSICAL REVIEW LETTERS 2012; 108:215002. [PMID: 23003271 DOI: 10.1103/physrevlett.108.215002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2012] [Indexed: 06/01/2023]
Abstract
Most of the work to date on plasma blobs found in the edge region of magnetic confinement devices is limited to 2D theory and simulations which ignore the variation of blob parameters along the magnetic field line. However, if the 2D convective rate of blobs is on the order of the growth rate of unstable drift waves, then drift wave turbulence can drastically alter the dynamics of blobs from that predicted by 2D theory. The density gradients in the drift plane that characterize the blob are mostly depleted during the nonlinear stage of drift waves resulting in a much more diffuse blob with a greatly reduced radial velocity. Sheath connected plasma blobs driven by effective gravity forces are considered in this Letter and it is found that the effects of resistive drift waves occur at earlier stages in the 2D motion for smaller blobs and in systems with a smaller effective gravity force. These conclusions are supported numerically by a direct comparison of 2D and 3D seeded blob simulations.
Collapse
Affiliation(s)
- Justin R Angus
- University of California, San Diego, La Jolla, California 92093, USA
| | | | | |
Collapse
|