Institute of Plasma Physics - project detail 00003

Multi-range tomographic system for transport studies in tokamak plasmas
Project ID:	GA202/09/1467
Provider:	Czech Science Foundation
Period:	Jan 01, 2009 - Dec 31, 2012
Principal Investigator:	Mgr. Vladimír Weinzettl, Ph.D.
Co-investigators	J. Mlynář, P. Bílková, J. Horáček, J. Adámek, R. Melich, D. Jareš, V. Piffl, D. Naydenkova, J. Havlíček
Aims of the project: Future realization of tokamak based fusion power plants will be possible only if a question of the particle and energy transport across the magnetic field toward the first wall and connected technical problems of extremely high heat loads to plasma-facing components will be satisfactorily solved.The main aim of this project is to contribute to an understanding of physics behind transport processes in magnetically confined plasmas using fast tomographic measurements in different spectral regions (bolometry, soft X-rays, visible light) and their comparison with results of other sufficiently fast plasma diagnostics. Prospective spatial resolution of the constructed tomographic systems will range in centimeter scales on plasma column at fewmicroseconds time base. Research will be done under the EURATOM Treaty in a broad international collaboration by a team of young scientists.
Progress/Results: The main aim of the project was to contribute to understanding of mechanisms behind transport processes in plasma of big experimental devices with magnetic confinement. The project was based on a broad international collaboration in the frame of European organizations EURATOM and EFDA (European Fusion Development Agreement). The tasks have been realized on the Czech COMPASS tokamak, on the JET tokamak in England as well as on the German tokamak ASDEX-Upgrade. On COMPASS at IPP AS CR, v.v.i., the unique, highly compact tomographic system suitable for measurements of fast processes observable in different spectral ranges has been designed and constructed there. The role of tearing mode instability has been analyzed and its characteristics have been measured. Sawteeth instability has been identified in discharges with a divertor plasma configuration and its characteristics have been measured. The characteristic flat shape of the measured density profile has been connected with a presence of this instability. The observed L- to H-mode transition has been always triggered by sawteeth instability. The consequent increase of both the core plasma density and temperature has been measured as a result of the decreased radial transport, thus, the increased energy and particle confinement time. On the German ASDEX Upgrade tokamak, the experiment with edge plasma biasing by the reciprocating manipulator has been realized. It has not been confirmed that a perturbation of the radial electric field can trigger the ELM type I instability, however, a local perturbation of the plasma density profile does. The edge plasma parameters in both L- and H-modes have been measured and compared using a combination of ball-pen and Langmuir probes located on the reciprocating manipulator. An agreement of the interchange turbulence model generating blobs in the edge plasma with the experiment has been demonstrated. Also, a dominance of electron density fluctuations over fluctuations of both temperature and plasma potential has been shown. By use of fast probe measurements of both electron density and temperature in ELMy H-mode, the concept of the filament structure of the ELM instability has been confirmed. On the JET tokamak in England, the algorithm of the pixel method based on Minimum Fischer Regularization has been optimized. Although, it is used for reconstructions of neutron radiation on JET, the code has been accommodated for the other tokamaks (COMPASS, TORE SUPRA, TCV) to perform a tomography of the local radiated power from data of both soft X-ray and bolometric diagnostics. Next, an analysis of the experimental data from the JET tokamak recording H-mode transitions from/to regimes of ELM type I and III has been done. The measured experimental scaling have been incorporated to the international database, which is used to create new experimental proposals on existing tokamaks as well as new scenarios for ITER and DEMO. The grant project has also contributed significantly to education of the new generation of scientists in the field of thermonuclear fusion. Many Czech as well as foreign students have been participated in the project (including 9 PhD students) resulting in four defended bachelor theses, three defended diploma theses and one defended PhD thesis. The milestones of the project were fulfilled.
Results:
Kočan M., Müller H. W., Nold B., Lunt T., Adámek J., Allan S.Y., Bernert M., Conway G.D., de Marné P., Eich T., Elmore S., Gennrich F.P., Herrmann A., Horáček J., Huang Z., Kallenbach A., Komm M., Maraschek M., Mehlmann F., Müller S., Ribeiro T.T., Rohde V., Schrittwieser R., Scott B., Stroth U., Suttrop W., Wolfrum E.: Intermittent transport across the scrape-off layer: latest results from ASDEX Upgrade. Nuclear Fusion 53 [7] (2013) 073047-073047. [ Abstract ] [ Link ]
Komm M., Dejarnac R., Gunn J. P., Pekarek Z.: Three-dimensional particle-in-cell simulations of gap crossings in castellated plasma-facing components in tokamaks. Plasma Physics and Controlled Fusion 55 [2] (2013) 025006-025006. [ Abstract ] [ Link ]
Kočan M., Müller H.W., Nold B., Lunt T., Adámek J., Allan S.Y., Bernert M., Conway G.D., de Marné P., Eich T., Elmore S., Gennrich F.P., Herrmann A., Horáček J., Huang Z., Kallenbach A., Komm M., Maraschek M., Mehlmann F., Müller S., Ribeiro T.T., Rohde V., Schrittwieser R., Scott B., Stroth U., Suttrop W., Wolfrum E.: Intermittent transport across the scrape-off layer: latest results from ASDEX Upgrade. Nuclear Fusion 53 [7] (2013) 073047-073047. [ Abstract ] [ Link ]
Aftanas M., Böhm P., Scannell R., Tripsky M., Weinzettl V., Hron M., Pánek R., Stöckel J., Walsh M., Bílková P.: Thomson scattering on COMPASS – commissioning and first data. Journal of Instrumentation 7 [1] (2012) C01074-C01074. [ Abstract ] [ Link ] [INTERNATIONAL CONFERENCE ON LASER AIDED PLASMA DIAGNOSTICS/15./. Jeju, 13.10.2011-19.10.2011]
Aftanas M., Böhm P., Bílková P., Weinzettl V., Zajac J., Žáček F., Stöckel J., Hron M., Pánek R., Scannell R., Walsh M.: High-resolution Thomson scattering system on the COMPASS tokamak: Evaluation of plasma parameters and error analysis. Review of Scientific Instruments 83 [10] (2012) 10E350-10E350. [ Abstract ] [ Link ] [Topical Conference High-Temperature Plasma Diagnostics/19./. Monterey, 06.05.2012-10.05.2012]
Mlynář J., Imríšek M., Weinzettl V., Odstrčil M., Havlíček J., Janky F., Alper B., Murari A.: Introducing minimum Fisher regularisation tomography to AXUV and soft x-ray diagnostic systems of the COMPASS tokamak. Review of Scientific Instruments 83 [10] (2012) 10E531-10E531. [ Abstract ] [ Link ] [Topical Conference High-Temperature Plasma Diagnostics/19./. Monterey, 06.05.2012-10.05.2012]
Weinzettl V., Imríšek M., Havlíček J., Mlynář J., Naydenkova D., Háček P., Hron M., Janky F., Sarychev D., Berta M., Bencze A., Szabolics T.: On Use of Semiconductor Detector Arrays on COMPASS Tokamak. World Academy of Science [77] (2012) 844-850. [ Abstract ] [ICPP 2012 : International Conference on Plasma Physics. Venice, 14.11.2012-16.11.2012]
Weinzettl V., Pánek R., Hron M., Stöckel J., Žáček F., Havlíček J., Bílková P., Naydenkova D., Háček P., Zajac J., Dejarnac R., Horáček J., Adámek J., Mlynář J., Janky F., Aftanas M., Böhm P., Brotánková J., Šesták D., Ďuran I., Melich R., Jareš D., Ghosh J., Anda B., Veres G., Szappanos A., Zoletnik S., Berta M., Shevchenko V. F., Scannell R., Walsh D., Müller H. W., Igochine V., Silva A., Manso M., Gomes R., Popov Tsv., Sarychev D., Kiselov V.K., Nanobashvili S.: Overview of the COMPASS diagnostics. Fusion Engineering and Design 86 [6-8] (2011) 1227-1231. [ Link ] [Symposium of Fusion Technology (SOFT-26). Porto, 27.09.2010-01.10.2010]
Komm M., Dejarnac R., Gunn J. P., Kirschner A., Litnovsky A., Matveev D., Pekarek Z.: Particle-in-cell simulations of plasma interaction with shaped and unshaped gaps in TEXTOR. Plasma Physics and Controlled Fusion 53 [11] (2011) 115004-115004. [ Link ]
Böhm P., Hron M., Kovar J., Sova J., Zvolanek M., Aftanas M., Bílková P., Pánek R., Walsh M.J.: Personnel protection during the operation of Thomson scattering laser system on COMPASS tokamak. Fusion Engineering and Design 86 [6-8] (2011) 699-702. [ Link ] [Symposium on Fusion Technology, SOFT-26/26th./. Porto, 27.09.2010-01.10.2010]
Naydenkova D., Weinzettl V., Stöckel J., Šesták D., Janky F.: The optical system for visible plasma radiation measurements in the COMPASS tokamak – design and testing. Acta Technica CSAV 56 [Topical Issue] (2011) T93-T100. [ Link ] [Symposium on plasma physics and technology/24th./. Prague, 14.06.2010-17.06.2010]
Naydenkova D., Janky F., Weinzettl V., Stöckel J., Šesták D., Ghosh J., Gomes R., Pereira T.: Measurements of Ion Temperature in the Edge Plasma of the COMPASS Tokamak. Proceedings of the 20th Annual Conference of Doctoral Students - WDS 2011. Prague : MATFYZPRESS, 2011 - (Šafránková, J.; Pavlů, J.) S. 233-236. ISBN 978-80-7378-185-9. - (WDS. 2). [Annual Conference of Doctoral Students - WDS 2011/20./. Prague (CZ), 31.05.2011-03.06.2011]
Háček P., Weinzettl V., Stöckel J., Anda G., Veres G., Zoletnik S., Berta M.: Diagnostic Lithium Beam System for COMPASS Tokamak. Proceedings of the 20th Annual Conference of Doctoral Students - WDS 2011. Prague : MATFYZPRESS, 2011 - (Šafránková, J.; Pavlů, J.) S. 215-220. ISBN 978-80-7378-185-9. - (WDS. 2). [ Abstract ] [ Link ] [Annual Conference of Doctoral Students - WDS 2011/20./. Prague (CZ), 31.05.2011-03.06.2011]
Aftanas M., Bílková P., Böhm P., Weinzettl V., Stöckel J., Hron M., Pánek R.: Measurement of the Laser Beam Position and Width for the Thomson Scattering Diagnostics on Tokamak COMPASS. Proceedings of the 20th Annual Conference of Doctoral Students - WDS 2011. Prague : MATFYZPRESS, 2011 - (Šafránková, J.; Pavlů, J.) S. 237-240. ISBN 978-80-7378-185-9. - (WDS. 2). [ Abstract ] [ Link ] [Annual Conference of Doctoral Students - WDS 2011/20./. Prague (CZ), 31.05.2011-03.06.2011]
Weinzettl V., Naydenkova D.I., Šesták D., Vlček J., Mlynář J., Melich R., Jareš D., Malot J., Sarychev D., Igochine V.: Design of multi-range tomographic system for transport studies in tokamak plasmas. Nuclear Instruments & Methods in Physics Research Section A 623 [2] (2010) 806-808. [ Abstract ] [ Link ] [International Conference on Frontiers in Diagnostic Technologies/1st./. Frascati, 25.11.2009-27.11.2009]
Bílková P., Aftanas M., Böhm P., Weinzettl V., Šesták D., Melich R., Stöckel J., Scannell R., Walsh M.: Design of new Thomson scattering diagnostic system on COMPASS tokamak. Nuclear Instruments & Methods in Physics Research Section A 623 [2] (2010) 656-659. [ Abstract ] [ Link ] [International Conference on Frontiers in Diagnostic Technologies/1st./. Frascati, 25.11.2009-27.11.2009]
Horáček J., Adámek J., Müller H. W., Seidl J., Nielsen A.H., Rohde V., Mehlmann F., Ionita C., Havlíčková E.: Interpretation of fast measurements of plasma potential, temperature and density. Nuclear Fusion 50 [10] (2010) 105001-105001. [ Abstract ] [ Link ]
Mlynář J., Weinzettl V., Bonheure G., Murari A.: Inversion techniques in the Soft X-Ray tomography of fusion plasmas: towards real-time applications. Fusion Science and Technology 58 [3] (2010) 733-741. [ Abstract ] [ Link ] [Workshop on Fusion Data Processing, Validation and Ananlyses/6th./. Madrid, 25.01.2010-27.01.2010]
Böhm P., Šesták D., Bílková P., Aftanas M., Weinzettl V., Hron M., Pánek R., Baillon L., Dunstan M.R., Naylor G., Walsh M.J.: Laser system for high resolution Thomson scattering diagnostics on the COMPASS tokamak. Review of Scientific Instruments 81 [10] (2010) 10D511-10D511. [ Abstract ] [ Link ] [TOPICAL CONFERENCE ON HIGH-TEMPERATURE PLASMA DIAGNOSTICS/18th./. Wildwood, New Jersey, 16.05.2010-20.05.2010]
Naydenkova D.I.G, Weinzettl V., Stöckel J., Šesták D., Janky F., Sedlák L.: Progress in Multichannel Optical System for Visible Plasma Radiation Measurements at COMPASS Tokamak. WDS 2010 - Proceedings of Contributed Papers. Prague : MATFYZPRESS, 2010 - (Šafránková, J.; Pavlů, J.) S. 18-21. ISBN 978-80-7378-140-8. - (WDS'10). [ Abstract ] [ Link ] [Annual Conference of Doctoral Students - WDS 2010 /19th./. Prague (CZ), 01.06.2010-04.06.2010]
Háček P., Weinzettl V., Stöckel J., Anda G., Veres G., Zoletnik S., Berta M.: Atomic Beam Probe Diagnostic for COMPASS Tokamak. WDS 2010 - Proceedings of Contributed Papers. Prague : MATFYZPRESS, 2010 - (Šafránková, J.; Pavlů, J.) S. 7-11. ISBN 978-80-7378-140-8. - (WDS'10). [ Abstract ] [ Link ] [Annual Conference of Doctoral Students - WDS 2010 /19th./. Prague (CZ), 01.06.2010-04.06.2010]
Mlynář J., Weinzettl V., Odstrčil M.: Progress in rapid tomography for the COMPASS tokamak. Bulletin of the American Physical Society 55 [15] (2010) GP9.0073-GP9.0073. [ Abstract ] [ Link ] [Annual Meeting of the APS Division of Plasma Physics/52th./. Chicago, Illinois, 08.11.2010-12.11.2010]
Bílková P., Melich R., Aftanas M., Böhm P., Šesták D., Jareš D., Weinzettl V., Stöckel J., Hron M., Pánek R., Scannell R., Walsh M.: Progress of development of Thomson scattering diagnostic system on COMPASS. Review of Scientific Instruments 81 [10] (2010) 10D531-10D531. [ Abstract ] [ Link ] [Topical Conference on High-Tempertaure Plasma Diagnostics/18th./. Wildwood, New Jersey, 16.05.2009-20.05.2009]
Aftanas M., Bílková P., Böhm P., Weinzettl V., Stöckel J., Hron M., Pánek R., Scannell R., Walsh M.: Data Acquisition System and Data Processing for the New Thomson Scattering System on the COMPASS Tokamak. WDS 2010 - Proceedings of Contributed Papers. Prague : MATFYZPRESS, 2010 - (Šafránková, J.; Pavlů, J.) S. 28-32. ISBN 978-80-7378-140-8. - (WDS'10). [ Abstract ] [ Link ] [Annual Conference of Doctoral Students - WDS 2010 /19th./. Prague (CZ), 01.06.2010-04.06.2010]
Müller H. W., Adámek J., Horáček J., Ionita C., Mehlmann F., Rohde V., Schrittwieser R.: Towards Fast Measurement of the Electron Temperature in the SOL of ASDEX Upgrade Using Swept Langmuir Probes. Contributions to Plasma Physics 50 [9] (2010) 847-853. [ Abstract ] [ Link ] [International Workshop on Electric Probes in Magnetized Plasmas/8th./. Innsbruck, 21.09.2009-24.09.2009]
Adámek J., Horáček J., Müller H. W., Rohde V., Ionita C., Schrittwieser R., Mehlmann F., Kurzan B., Stöckel J., Dejarnac R., Weinzettl V., Seidl J., Peterka M.: Ball-Pen Probe Measurements in L-Mode and H-Mode on ASDEX Upgrade. Contributions to Plasma Physics 50 [9] (2010) 854-859. [ Abstract ] [ Link ] [International Workshop on Electric Probes in Magnetized Plasmas/8th./. Innsbruck, 21.09.2009-24.09.2009]
Mlynář J., Bonheure G., Murari A., Popovichev S., JET EFDA Contributors.: Experimental studies of spatial characteristics of tritium transport at JET. Contributed Papers 36th European Physical Society Conference on Plasma Physics. Sofia : European Physical Society, 2009 - (Mateev, M.; Benova, E.) P2.154. ISBN 2-914771-61-4. - (Europhysics conference abstracts). [ Abstract ] [ Link ] [European Physical Society Conference on Plasma Physics /36th./. Sofia (BG), 29.06.2009-03.07.2009]