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245 results on '"Pereverzev, G."'

2. The European transport solver

Author

Coster, D.P., Basiuk, V., Pereverzev, G., Kalupin, D., Zagorksi, R., Stankiewicz, R., Huynh, P., and Imbeaux, F.

Subjects
Magnetic flux -- Measurement, Plasma devices -- Design and construction, Tokamaks -- Models, Business, Chemistry, Electronics, Electronics and electrical industries
Published
2010

3. Performance Projections For The Lithium Tokamak Experiment (LTX)

Author

Majeski, R., primary, Berzak, L., additional, Gray, T., additional, Kaita, R., additional, Kozub, T., additional, Levinton, F., additional, Lundberg, D. P., additional, Manickam, J., additional, Pereverzev, G. V., additional, Snieckus, K., additional, Soukhanovskii, V., additional, Spaleta, J., additional, Stotler, D., additional, Strickler, T., additional, Timberlake, J., additional, Yoo, J., additional, and Zakharov, L., additional

Published
2009
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4. On the energy transport in internal transport barriers of RFP plasmas

Author

Lorenzini, R, Alfier, A, Auriemma, F, Fassina, A, Franz, P, Innocente, P, Lopez-Bruna, D, Martines, E, Momo, B, Pereverzev, G, Piovesan, P, Spizzo, G, Spolaore, M, Terranova, D, Lorenzini R, Alfier A, Auriemma F, Fassina A, Franz P, Innocente P, Lopez-Bruna D, Martines E, Momo B, Pereverzev G, Piovesan P, Spizzo G, Spolaore M, Terranova D, Lorenzini, R, Alfier, A, Auriemma, F, Fassina, A, Franz, P, Innocente, P, Lopez-Bruna, D, Martines, E, Momo, B, Pereverzev, G, Piovesan, P, Spizzo, G, Spolaore, M, Terranova, D, Lorenzini R, Alfier A, Auriemma F, Fassina A, Franz P, Innocente P, Lopez-Bruna D, Martines E, Momo B, Pereverzev G, Piovesan P, Spizzo G, Spolaore M, and Terranova D

Abstract

Single helical axis (SHAx) states obtained in high current reversed field pinch (RFP) plasmas feature an internal transport barrier delimiting the hot helical core region. The electron temperature jump across this region, and the related temperature gradient, display a clear relationship with the normalized amplitude of the secondary MHD modes. A transport analysis performed with the ASTRA code, taking into account the helical geometry, yields values of the thermal conductivity in the barrier region as low as 5 m(2) s(-1). The thermal conductivity is also related to the secondary mode amplitude. Since such amplitude is reduced when plasma current is increased, it is expected that higher current plasmas will display even steeper thermal gradients and hotter helical cores.

Published
2012

5. The European Integrated Tokamak Modelling (ITM) effort: achievements and first physics results

Author

Falchetto, G.L., Coster, D., Coelho, R., Scott, B.D., Figini, L., Kalupin, D., Nardon, E., Nowak, S., Alves, L.L., Artaud, J.F., Basiuk, V., Bizarro, JoãoP.S., Boulbe, C., Dinklage, A., Farina, D., Faugeras, B., Ferreira, J., Figueiredo, A., Huynh, P., Imbeaux, F., Ivanova-Stanik, I., Jonsson, T., Klingshirn, H.-J., Konz, C., Kus, A., Marushchenko, N.B., Pereverzev, G., Owsiak, M., Poli, E., Peysson, Y., Reimer, R., Signoret, J., Sauter, O., Stankiewicz, R., Strand, P., Voitsekhovitch, I., Westerhof, E., Zok, T., Zwingmann, W., contributors, ITM-TF, Team, ASDEXUpgrade, Contributors, JET-EFDA, Institut de Recherche sur la Fusion par confinement Magnétique (IRFM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Max-Planck-Institut für Plasmaphysik [Garching] (IPP), Instituto de Plasmas e Fusão Nuclear [Lisboa] (IPFN), Instituto Superior Técnico, Universidade Técnica de Lisboa (IST), Istituto di Fisica del Plasma, EURATOM-ENEA-CNR Association, Consiglio Nazionale delle Ricerche [Roma] (CNR), European Fusion Development Agreement [Garching bei München] ( EFDA-CSU), Control, Analysis and Simulations for TOkamak Research (CASTOR), Inria Sophia Antipolis - Méditerranée (CRISAM), Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Laboratoire Jean Alexandre Dieudonné (JAD), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Jean Alexandre Dieudonné (JAD), Association EURATOM-CEA (CEA/DSM/DRFC), Institute of Plasma Physics and Laser Microfusion [Warsaw] (IPPLM), Fusion Plasma Physics [Stockholm], Royal Institute of Technology [Stockholm] (KTH ), Poznan Supercomputing and Networking Center (PSNC), Ecole Polytechnique Fédérale de Lausanne (EPFL), Department of Earth and Space Sciences [Göteborg], Chalmers University of Technology [Göteborg], Culham Science Centre [Abingdon], Dutch Institute for Fundamental Energy Research [Nieuwegein] (DIFFER), Research & Innovation [Brussels], European Commission [Brussels], National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Laboratoire Jean Alexandre Dieudonné (LJAD), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), Laboratoire Jean Alexandre Dieudonné (LJAD), ITM-TF Contributors, ASDEX Upgrade Team, Max Planck Institute for Plasma Physics, Max Planck Society, and JET-EFDA Contributors

Subjects
Nuclear and High Energy Physics, Tokamak, 7. Clean energy, 01 natural sciences, 010305 fluids & plasmas, law.invention, ASDEX Upgrade, law, Physics::Plasma Physics, Benchmark (surveying), 0103 physical sciences, Fysik, Aerospace engineering, 010306 general physics, ComputingMilieux_MISCELLANEOUS, Physics, business.industry, turbulence, Magnetic confinement fusion, Fluid mechanics, Condensed Matter Physics, Data structure, simulation, [INFO.INFO-MO]Computer Science [cs]/Modeling and Simulation, Workflow, Physical Sciences, integrated modelling, transport, code verification, Magnetohydrodynamics, business
Abstract

A selection of achievements and first physics results are presented of the European Integrated Tokamak Modelling Task Force (EFDA ITM-TF) simulation framework, which aims to provide a standardized platform and an integrated modelling suite of validated numerical codes for the simulation and prediction of a complete plasma discharge of an arbitrary tokamak. The framework developed by the ITM-TF, based on a generic data structure including both simulated and experimental data, allows for the development of sophisticated integrated simulations (workflows) for physics application.The equilibrium reconstruction and linear magnetohydrodynamic (MHD) stability simulation chain was applied, in particular, to the analysis of the edgeMHDstability of ASDEX Upgrade type-I ELMy H-mode discharges and ITER hybrid scenario, demonstrating the stabilizing effect of an increased Shafranov shift on edge modes. Interpretive simulations of a JET hybrid discharge were performed with two electromagnetic turbulence codes within ITM infrastructure showing the signature of trapped-electron assisted ITG turbulence. A successful benchmark among five EC beam/ray-tracing codes was performed in the ITM framework for an ITER inductive scenario for different launching conditions from the equatorial and upper launcher, showing good agreement of the computed absorbed power and driven current. Selected achievements and scientific workflow applications targeting key modelling topics and physics problems are also presented, showing the current status of the ITM-TF modelling suite. QC 20140505. Correction in: Nuclear Fusion, vol. 54, issue 9, Article Number. 099501WOS: 000341966700017, DOI: 10.1088/0029-5515/54/9/099501

Published
2014
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6. Corrigendum: The European Integrated Tokamak Modelling (ITM) effort: achievements and first physics results (vol 54, 043018, 2014)

Author

Falchetto, G. L., Coster, D., Coelho, R., Scott, B. D., Figini, L., Kalupin, D., Nardon, E., Nowak, S., Alves, L. L., Artaud, J. F., Basiuk, V., Bizarro, Joao P. S., Boulbe, C., Dinklage, A., Farina, D., Faugeras, B., Ferreira, J., Figueiredo, A., Huynh, Ph., Imbeaux, F., Ivanova-Stanik, I., Jonsson, T., Klingshirn, H. -J., Konz, C., Kus, A., Marushchenko, N. B., Pereverzev, G., Owsiak, M., Poli, E., Peysson, Y., Reimer, R., Signoret, J., Sauter, O., Stankiewicz, R., Strand, P., Voitsekhovitch, I., Westerhof, E., Zok, T., and Zwingmann, W.

Subjects
integrated modelling, turbulence, transport, code verification, simulation
Abstract

References [59-61] were incorrectly cited in Falchetto G.L. et al 2014 (Nucl. Fusion 54 043018), the corresponding paragraphs on page 14-15 should be replaced ...

Published
2014
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7. Novel free-boundary equilibrium and transport solver with theory-based models and its validation against ASDEX Upgrade current ramp scenarios (invited paper)

Author

Fable, E., Angioni, C., Casson, F. J., Told, D., Ivanov, A. A., Jenko, F., McDermott, R. M., Medvedev, S. Yu., Pereverzev, G. V., Ryter, F., Treutterer, W., Viezzer, E., ASDEX Upgrade Team, and ASDEX Upgrade Team

Subjects
Physics, Coupling, Safety factor, Tokamak, Mechanics, Plasma, Condensed Matter Physics, ASTRA, law.invention, Nuclear Energy and Engineering, ASDEX Upgrade, Physics::Plasma Physics, law, Current (fluid), Scaling
Abstract

Tokamak scenario development requires an understanding of the properties that determine the kinetic profiles in non-steady plasma phases and of the self-consistent evolution of the magnetic equilibrium. Current ramps are of particular interest since many transport-relevant parameters explore a large range of values and their impact on transport mechanisms has to be assessed. To this purpose, a novel full-discharge modelling tool has been developed, which couples the transport code ASTRA (Pereverzev et al 1991 IPP Report 5/42) and the free boundary equilibrium code SPIDER (Ivanov et al 2005 32nd EPS Conf. on Plasma Physics vol 29C (ECA) P-5.063 and http://epsppd.epfl.ch/Tarragona/pdf/P5_063.pdf), utilizing a specifically designed coupling scheme. The current ramp-up phase can be accurately and reliably simulated using this scheme, where a plasma shape, position and current controller is applied, which mimics the one of ASDEX Upgrade. Transport of energy is provided by theory-based models (e.g. TGLF (Staebler et al 2007 Phys. Plasmas 14 055909)). A recipe based on edge-relevant parameters (Scott 2000 Phys. Plasmas 7 1845) is proposed to resolve the low current phase of the current ramps, where the impact of the safety factor on micro-instabilities could make quasi-linear approaches questionable in the plasma outer region. Current ramp scenarios, selected from ASDEX Upgrade discharges, are then simulated to validate both the coupling with the free-boundary evolution and the prediction of profiles. Analysis of the underlying transport mechanisms is presented, to clarify the possible physics origin of the observed L-mode empirical energy confinement scaling. The role of toroidal micro-instabilities (ITG, TEM) and of non-linear effects is discussed.

Published
2013

8. The European Integrated Tokamak Modelling Effort:Achievements and First Physics Results

Author

Falchetto, G., Coster, D., Coelho, R., Strand, P., Eriksson, L. G., Basiuk, V., Farina, D., Imbeaux, F., Jonsson, T., Konz, C., Litaudon, X., Manduchi, G., Nielsen, Anders Henry, Ottaviani, M., Paccagnella, R., Pereverzev, G., Scott, B., Tskhakaya, D., Vlad, G., Voitsekhovitch, I., Guillerminet, B., Kalupin, D., Giovannozzi, E., Klingshirn, H.J., Yadikin, D., and Zwingmann, W.

Subjects
ComputingMilieux_LEGALASPECTSOFCOMPUTING
Published
2012

9. The European Integrated Tokamak Modelling (ITM) Effort: Achievements and First Physics Results

Author

Falchetto G., Coster D., Coelho R., Strand P., Eriksson L. G., Basiuk V., Farina D., Imbeaux F., Jonsson T., Konz C., Litaudon X., Manduchi G., Nielsen A. H., Ottaviani M., Paccagnella R., Pereverzev G., Scott B., Tskhakaya D., Vlad G., Voitsekhovitch I., Guillerminet B., Kalupin D., Giovannozzi E., Klingshirn H. J., Yadikin D., and Zwingmann W.

Subjects
____
Abstract

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Published
2012

13. Axially Symmetric Divertor Experiment (ASDEX) Upgrade Team (vol 81, 033507, 2010)

Author

Adamek, J., Angioni, C., Antar, G., Atanasiu, C.V., Balden, M., Becker, W., Behler, K., Behringer, K., Bergmann, A., Bilato, R., Bobkov, V., Boom, J., Bottino, A., Brambilla, M., Braun, F., Brüdgam, M., Buhler, A., Chankin, A., Classen, I., Conway, G.D., Coster, D.P., de Marne, P., D'Inca, R., Dodt, D., Doerk-Bendig, H., Drube, R., Dux, R., Eich, T., Endstrasser, N., Engelhardt, K., Fahrbach, H.-U., Fattorini, L., Fischer, R., Forest, C., Fuchs, J.C., Gal, K., Munoz, M.G., Adamov, M.G., Giannone, L., Görler, L., Gori, S., da Graca, S., Greuner, H., Gruber, O., Gude, A., Günter, S., Haas, G., Hammer, N., Hauff, T., Heinemann, B., Herrmann, A., Hicks, N., Hobirk, J., Hölzl, M., Holtum, D., Hopf, C., Huart, M., Igochine, V., Janzer, M., Jenko, F., Kagarmanov, A., Kallenbach, A., Kammel, A., Kalvin, S., Kardaun, O., Kaufmann, M., Kick, M., Kirk, A., Klingshirn, H.-J., Koscis, G., Kollotzek, H., Konz, C., Krieger, K., Kurki-Suonio, T., Kurzan, B., Lackner, K., Lang, P.T., Langer, B., Lauber, P., Laux, M., Leuterer, F., Likonen, J., Liu, L., Lohs, A., Lunt, T., Lyssoivan, A., Mank, K., Manso, M.-E., Mantsinen, M., Maraschek, M., Martin, P., Mayer, M., McCarthy, P., McCormick, K., McDermott, R., Meister, H., Meo, Fernando, Merkel, P., Merkel, R., Mertens, V., Merz, F., Meyer, H., Mlynek, A., Monaco, F., Müller, H.-W., Münich, M., Murmann, H., Neu, G., Neu, R., Neuhauser, J., Nold, B., Noterdaeme, J.M., Pautasso, G., Pereverzev, G., Poli, E., Potzel, S., Püschel, M., Pütterich, T., Raupp, G., Reich, M., Reiter, B., Ribeiro, T., Riedl, R., Rohde, V., Roth, J., Rott, M., Ryter, F., Sandmann, W., Santos, J., Sassenberg, K., Sauter, P., Scarabosio, A., Schall, G., Schmid, K., Schneider, P., Schneider, W., Schrittwieser, R., Schweinzer, J., Scott, B., Seidel, U., Sempf, M., Serra, F., Sertoli, M., Siccinio, M., Sigalov, A., Silva, A., Speth, E., Stäbler, A., Stadler, R., Steuer, K.-H., Stober, J., Streibl, B., Strumberger, E., Suttrop, W., Tardini, G., Tichmann, C., Treutterer, W., Urso, L., Vainonen-Ahlgren, E., Varela, P., Vorpahl, C., Wagner, D., Wigger, C., Wischmeier, M., Wolfrum, E., Würsching, E., Yadikin, D., Yu, Q., Zasche, D., Zehetbauer, T., Zilker, M., and Zohm, H.

Subjects
Fusion energy, Fusionsenergi, Fusionsenergiforskning
Published
2010
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15. A generic data structure for integrated modelling of tokamak physics and subsystems

Author

Imbeaux F., Lister J. B., Huysmans G.T.A, Zwingmann W., Airaj M., Appel L., Basiuk V., Coster D., Eriksson L.-G., Guillerminet B., Kalupin D., Konz C., Manduchi G., Ottaviani M., Pereverzev G., Peysson Y., Sauter O., Signoret J., Strand P., ITM-TF work programme contributors, Institut de Recherche sur la Fusion par confinement Magnétique (IRFM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Ecole Polytechnique Fédérale de Lausanne (EPFL), European Commission, DG Joint Research Centre, EURATOM/UKAEA Fusion Association, Culham Science Centre [Abingdon], Max-Planck-Institut für Plasmaphysik [Garching] (IPP), European Fusion Development Agreement [Garching bei München] ( EFDA-CSU), Associazione Euratom-ENEA sulla Fusione, EURATOM-VR Fusion Assoc., Chalmers University of Technology [Göteborg], and European Project: 211804,EC:FP7:INFRA,FP7-INFRASTRUCTURES-2007-1,EUFORIA(2008)

Subjects
Tokamak, Computer science, [INFO.INFO-DS]Computer Science [cs]/Data Structures and Algorithms [cs.DS], integrated simulation, General Physics and Astronomy, Integrated modelling, 01 natural sciences, computer framework, 010305 fluids & plasmas, law.invention, Workflows, law, 0103 physical sciences, Plasma simulation, 010306 general physics, nuclear fusion, Simulation, [PHYS]Physics [physics], Data model, business.industry, Modular design, Data structure, [INFO.INFO-MO]Computer Science [cs]/Modeling and Simulation, Variety (cybernetics), Workflow, Hardware and Architecture, Software deployment, Systems engineering, Dynamical simulation, business
Abstract

International audience; The European Integrated Tokamak Modelling Task Force (ITM-TF) is developing a new type of fully modular and flexible integrated tokamak simulator, which will allow a large variety of simulation types. This ambitious goal requires new concepts of data structure and workflow organisation, which are described for the first time in this paper. The backbone of the system is a physics-and workflow-oriented data structure which allows for the deployment of a fully modular and flexible workflow organisation. The data structure is designed to be generic for any tokamak device and can be used to address physics simulation results, experimental data (including description of subsystem hardware) and engineering issues.

Published
2010
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16. The European Integrated Tokamak Modelling (ITM) effort : achievements and first physics results

Author

Falchetto, G. L., Coster, D., Coelho, R., Scott, B. D., Figini, L., Kalupin, D., Nardon, E., Nowak, S., Alves, L. L., Artaud, J. F., Basiuk, V., Bizarro, Jao P. S., Boulbe, C., Dinklage, A., Farina, D., Faugeras, B., Ferreira, J., Figueiredo, A., Huynh, Ph, Imbeaux, F., Ivanova-Stanik, I., Johnson, Thomas, Klingshirn, H-J, Konz, C., Kus, A., Marushchenko, N. B., Pereverzev, G., Owsiak, M., Poli, E., Peysson, Y., Reimer, R., Signoret, J., Sauter, O., Stankiewicz, R., Strand, P., Voitsekhovitch, I., Westerhof, E., Zok, T., Zwingmann, W., Falchetto, G. L., Coster, D., Coelho, R., Scott, B. D., Figini, L., Kalupin, D., Nardon, E., Nowak, S., Alves, L. L., Artaud, J. F., Basiuk, V., Bizarro, Jao P. S., Boulbe, C., Dinklage, A., Farina, D., Faugeras, B., Ferreira, J., Figueiredo, A., Huynh, Ph, Imbeaux, F., Ivanova-Stanik, I., Johnson, Thomas, Klingshirn, H-J, Konz, C., Kus, A., Marushchenko, N. B., Pereverzev, G., Owsiak, M., Poli, E., Peysson, Y., Reimer, R., Signoret, J., Sauter, O., Stankiewicz, R., Strand, P., Voitsekhovitch, I., Westerhof, E., Zok, T., and Zwingmann, W.

Abstract

A selection of achievements and first physics results are presented of the European Integrated Tokamak Modelling Task Force (EFDA ITM-TF) simulation framework, which aims to provide a standardized platform and an integrated modelling suite of validated numerical codes for the simulation and prediction of a complete plasma discharge of an arbitrary tokamak. The framework developed by the ITM-TF, based on a generic data structure including both simulated and experimental data, allows for the development of sophisticated integrated simulations (workflows) for physics application.The equilibrium reconstruction and linear magnetohydrodynamic (MHD) stability simulation chain was applied, in particular, to the analysis of the edgeMHDstability of ASDEX Upgrade type-I ELMy H-mode discharges and ITER hybrid scenario, demonstrating the stabilizing effect of an increased Shafranov shift on edge modes. Interpretive simulations of a JET hybrid discharge were performed with two electromagnetic turbulence codes within ITM infrastructure showing the signature of trapped-electron assisted ITG turbulence. A successful benchmark among five EC beam/ray-tracing codes was performed in the ITM framework for an ITER inductive scenario for different launching conditions from the equatorial and upper launcher, showing good agreement of the computed absorbed power and driven current. Selected achievements and scientific workflow applications targeting key modelling topics and physics problems are also presented, showing the current status of the ITM-TF modelling suite., QC 20140505. Correction in: Nuclear Fusion, vol. 54, issue 9, Article Number. 099501WOS: 000341966700017, DOI: 10.1088/0029-5515/54/9/099501

Published
2014
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17. Overview of ASDEX upgrade results

Author

Zohm H., Adamek J., Angioni C., Antar G., Atanasiu C. V., Balden M., Becker W., Behler K., Behringer K., Bergmann A., Bertoncelli T., Bilato R., Bobkov V., Boom J., Bottino A., Brambilla M., Braun F., Bruedgam M., Buhler A., Chankin A., Classen I., Conway G. D., Coster D. P., de Marne P., D'Inca R., Drube R., Dux R., Eich T., Engelhardt K., Esposito B., Fahrbach H-U., Fattorini L., Fink J., Fischer R., Flaws A., Foley M., Forest C., Fuchs J. C., Gal K., Munoz M. Garcia, Adamov M. Gemisic, Giannone L., Goerler T., Gori S., da Graca S., Granucci G., Greuner H., Gruber O., Gude A., Guenter S., Haas G., Hahn D., Harhausen J., Hauff T., Heinemann B., Herrmann A., Hicks N., Hobirk J., Hoelzl M., Holtum D., Hopf C., Horton L., Huart M., Igochine V., Janzer M., Jenko F., Kallenbach A., Kalvin S., Kardaun O., Kaufmann M., Kick M., Kirk A., Klingshirn H-J., Koscis G., Kollotzek H., Konz C., Krieger K., Kurki-Suonio, Kurzan B., Lackner K., Lang P. T., Langer B., Lauber P., Laux M., Leuterer F., Likonen J., Liu L., Lohs A., Lunt T., Lyssoivan A., Maggi C. F., Manini A., Mank K., Manso M-E., Mantsinen M., Maraschek M., Martin P., Mayer M., McCarthy P., McCormick K., Meister H., Meo F., Merkel P., Merkel R., Mertens V., Merz F., Meyer H., Mlynek A., Monaco F., Mueller H-W., Muenich M., Murmann H., Neu G., Neu R., Neuhauser J., Nold B., Noterdaeme J-M., Pautasso G., Pereverzev G., Poli E., Potzel, Pueschel M., Puetterich T., Pugno R., Raupp G., Reich M., Reiter B., Ribeiro T., Riedl R., Rohde V., Roth J., Rott M., Ryter F., Sandmann W., Santos J., Sassenberg, Sauter P., Scarabosio A., Schall G., Schilling H-B., Schirmer J., Schmid A., Schmid K., Schneider W., Schramm G., Schrittwieser R., Schustereder W., Schweinzer J., Schweizer S., Scott B., Seidel U., Sempf M., Serra F., Sertoli M., Siccinio M., Sigalov A., Silva A., Sips C. C., Speth E., Staebler A., Stadler R., Steuer K-H., Stober J., Streibl B., Strumberger E., Suttrop W., Tardini G., Tichmann C., Treutterer W., Troester C., Urso L., Vainonen-Ahlgren E., Varela P., Vermare L., Volpe F., Wagner D., Wigger C., Wischmeier M., Wolfrum E., Wuersching E., Yadikin D., Yu Q., Zasche D., Zehetbauer T., and Zilker M.

Subjects
Nuclear and High Energy Physics, Materials science, Nuclear engineering, Condensed Matter Physics, 7. Clean energy, 01 natural sciences, 010305 fluids & plasmas, ASDEX Upgrade, ITER, 0103 physical sciences, tokamak physics, 010306 general physics, DEMO, nuclear fusion
Abstract

ASDEX Upgrade was operated with a fully W-covered wall in 2007 and 2008. Stationary H-modes at the ITER target values and improved H-modes with H up to 1.2 were run without any boronization. The boundary conditions set by the full W wall (high enough ELM frequency, high enough central heating and low enough power density arriving at the target plates) require significant scenario development, but will apply to ITER as well. D retention has been reduced and stationary operation with saturated wall conditions has been found. Concerning confinement, impurity ion transport across the pedestal is neoclassical, explaining the strong inward pinch of high-Z impurities in between ELMs. In improved H-mode, the width of the temperature pedestal increases with heating power, consistent with a β1/2pol,ped scaling. In the area of MHD instabilities, disruption mitigation experiments using massive Ne injection reach volume averaged values of the total electron density close to those required for runaway suppression in ITER. ECRH at the q = 2 surface was successfully applied to delay density limit disruptions. The characterization of fast particle losses due to MHD has shown the importance of different loss mechanisms for NTMs, TAEs and also beta-induced Alfven eigenmodes (BAEs). Specific studies addressing the first ITER operational phase show that O1 ECRH at the HFS assists reliable low-voltage breakdown. During ramp-up, additional heating can be used to vary li to fit within the ITER range. Confinement and power threshold in He are more favourable than in H, suggesting that He operation could allow us to assess H-mode operation in the non-nuclear phase of ITER operation.

Published
2009
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18. Extrapolation of ASDEX Upgrade H-mode discharges to ITER

Author

Tardini, G., Horton, L., Kardaun, O., Maggi, C., Peeters, A., Pereverzev, G., Sips, A., Stober, J., and ASDEX Upgrade Team

Subjects
Physics, Nuclear and High Energy Physics, Nuclear engineering, Extrapolation, Magnetic confinement fusion, Plasma, Fusion power, Condensed Matter Physics, Nuclear physics, ASDEX Upgrade, Physics::Plasma Physics, Figure of merit, Sensitivity (control systems), Scaling
Abstract

In this paper we discuss a procedure to evaluate the fusion performance of ASDEX Upgrade discharges scaled up to ITER. The kinetic profile shape is taken from the measured profiles. Multiplication factors are used to obtain a fixed Greenwald fraction and an ITER normalized thermal pressure as in the corresponding ASDEX Upgrade discharge. The toroidal field and the plasma geometry are taken from the ITER-FEAT design (scenario 2), whereas q95 is taken from the experiment. The confinement time is inferred assuming that the measured H-factor with respect to several existing scaling laws also holds for ITER. While retaining the information contained in the multi-machine databases underlying the different scaling laws, this approach adds profile effects and confinement improvement with respect to the ITER baseline, thus including recent experimental evidence such as the prediction of peaked density profiles in ITER. Under this set of assumptions, of course not unique, we estimate the ITER performance on the basis of a wide database of ASDEX Upgrade H-mode discharges, in terms of fusion power, fusion gain and triple product. According to the three scalings considered, there is a finite probability of reaching ignition, while more than half of the discharges require less auxiliary power than the one foreseen for ITER. For all the scaling laws, high values of the thermal ?N up to 2.4 are accessible. A sensitivity study gives an estimate of the accuracy of the extrapolation. The impact of different levels of tungsten concentration on the fusion performance is also studied in this paper. This scaling method is used to verify some common 0D figures of merit of ITER's fusion performance.

Published
2009

19. Integrated modelling of ITER reference scenarios

Author

Parail, V., Belo, P., Boerner, P., Bonnin, X., Corrigan, G., Coster, D., Ferreira, J., Foster, A., Garzotti, L., Hogeweij, G.M. D., Houlberg, W., Imbeaux, F., Johner, J., Kochl, F., Kotov, V., Lauro-Taroni, L., Litaudon, X., Lonnroth, J., Pereverzev, G., Peysson, Y., Saibene, G., Sartori, R., Schneider, M., Sips, G., Strand, P., Tardini, G., Valovic, M., Wiesen, S., Wischmeier, M., and Zagorski, R.

Abstract

The ITER Scenario Modelling Working Group (ISM WG) is organized within the European Task Force on Integrated Tokamak Modelling (ITM-TF). The main responsibility of the WG is to advance a pan-European approach to integrated predictive modelling of ITER plasmas with the emphasis on urgent issues, identified during the ITER Design Review. Three major topics are discussed, which are considered as urgent and where the WG has the best possible expertize. These are modelling of current profile control, modelling of density control and impurity control in ITER (the last two topics involve modelling of both core and SOL plasma). Different methods of heating and current drive are tested as controllers for the current profile tailoring during the current ramp-up in ITER. These include Ohmic, NBI, ECRH and LHCD methods. Simulation results elucidate the available operational margins and rank different methods according to their ability to meet different requirements. A range of 'ITER-relevant' plasmas from existing tokamaks were modelled. Simulations confirmed that the theory-based transport model, GLF23, reproduces the density profile reasonably well and can be used to assess ITER profiles with both pellet injection and gas puffing. In addition, simulations of the SOL plasma were launched using both H-mode and L-mode models for perpendicular transport within the edge barrier and in the SOL. Finally, an integrated approach was also used for the predictive modelling of impurity accumulation in ITER. This includes helium ash, extrinsic impurities (such as argon) and impurities coming from the wall (including tungsten). The relative importance of anomalous and neo-classical pinch contributions towards impurity penetration through the edge transport barrier and further accumulation in the core was assessed.

Published
2009

22. Plasma wall interaction and its implication in an all tungsten divertor tokamak. Invited Paper

Author

Neu, R., Balden, M., Bobkov, V., Dux, R., Gruber, O., Herrmann, A., Kallenbach, A., Kaufmann, M., Maggi, C. F., Maier, H., Müller, H. W., Pütterich, T., Pugno, R., Rohde, V., Sips, A. C. C., Stober, J., Suttrop, W., Angioni, C., Atanasiu, C. V., Becker, W., Behler, K., Behringer, K., Bergmann, A., Bertoncelli, T., Bilato, R., Bottino, A., Brambilla, M., Braun, F., Buhler, A., Chankin, A., Conway, G., Coster, D. P., de Marne, P., Dietrich, S., Dimova, K., Drube, R., Eich, T., Engelhardt, K., Fahrbach, H.-U., Fantz, U., Fattorini, L., Fink, J., Fischer, R., Flaws, A., Franzen, P., Fuchs, J. C., Gal, K., Garcia Munoz, M., Gemisic-Adamov, M., Giannone, L., Gori, S., da Graca, S., Greuner, H., Gude, A., Günter, S., Haas, G., Harhausen, J., Heinemann, B., Hicks, N., Hobirk, J., Holtum, D., Hopf, C., Horton, L., Huart, M., Igochine, V., Kalvin, S., Kardaun, O., Kick, M., Kocsis, G., Kollotzek, H., Konz, C., Krieger, K., Kurki-Suonio, T., Kurzan, B., Lackner, K., Lang, P. T., Lauber, P., Laux, M., Likonen, J., Liu, L., Lohs, A., Mank, K., Manini, A., Manso, M.-E., Maraschek, M., Martin, P., Martin, Y., Mayer, M., McCarthy, P., McCormick, K., Meister, H., Meo, F., Merkel, P., Merkel, R., Mertens, V., Merz, F., Meyer, H., Mlynek, M., Monaco, F., Murmann, H., Neu, G., Neuhauser, J., Nold, B., Noterdaeme, J.-M., Pautasso, G., Pereverzev, G., Poli, E., Pueschel, M., Raupp, G., Reich, M., Reiter, B., Ribeiro, T., Riedl, R., Roth, J., Rott, M., Ryter, F., Sandmann, W., Santos, J., Sassenberg, K., Scarabosio, A., Schall, G., Schirmer, J., Schmid, A., Schneider, W., Schramm, G., Schrittwieser, R., Schustereder, W., Schweinzer, J., Schweizer, S., Scott, B., Seidel, U., Serra, F., Sertoli, M., Sigalov, A., Silva, A., Speth, E., Stäbler, A., Steuer, K.-H., Strumberger, E., Tardini, G., Tichmann, C., Treutterer, W., Tröster, C., Urso, L., Vainonen-Ahlgren, E., Varela, P., Vermare, L., Wagner, D., Wischmeier, M., Wolfrum, E., Würsching, E., Yadikin, D., Yu, Q., Zasche, D., Zehetbauer, T., Zilker, M., and Zohm, H.

Published
2007

24. Particle and impurity transport in the Axial Symmetric Divertor Experiment Upgrade and the Joint European Torus, experimental observations and theoretical understanding

Author

Angioni, C., Carraro, L., Dannert, T., Dubuit, N., Dux, R., Christoph Fuchs, Garbet, X., Garzotti, L., Giroud, C., Guirlet, R., Jenko, F., Kardaun, O. J. W. F., Lauro-Taroni, L., Mantica, P., Maslov, M., Naulin, V., Neu, R., Peeters, A. G., Pereverzev, G., Puiatti, M. E., Pütterich, T., Stober, J., Valovic, M., Valisa, M., Weisen, H., Zabolotsky, A., Asdex, Upgrade Team, Jet Efda, Contributors, ASDEX Upgrade Team, and JET EFDA Contributors

Subjects
Physics, Jet (fluid), Tokamak, Field (physics), Divertor, Joint European Torus, Plasma, ANOMALOUS PINCH, Condensed Matter Physics, ASDEX UPGRADE, law.invention, Nuclear physics, Upgrade, TOKAMAK PLASMAS, JET, law, H-MODE PLASMAS, DENSITY PROFILE, Particle
Abstract

Experimental observations on core particle and impurity transport from the Axial Symmetric Divertor Experiment Upgrade [O. Gruber, H.-S. Bosch, S. Gunter , Nucl Fusion 39, 1321 (1999)] and the Joint European Torus [J. Pamela, E. R. Solano, and JET EFDA Contributors, Nucl. Fusion 43, 1540 (2003)] tokamaks are reviewed and compared. Robust general experimental behaviors observed in both the devices and related parametric dependences are identified. The experimental observations are compared with the most recent theoretical results in the field of core particle transport. (C) 2007 American Institute of Physics.

Published
2007
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30. Overview of ASDEX Upgrade resultsâ€'development of integrated operating scenarios for ITER

Author

Guenter, S., Angioni, C., Apostoliceanu, M., Atanasiu, C., Balden, M., Becker, G., Becker, W., Behler, K., Behringer, K., Bergmann, A., Bilato, R., Bizyukov, I., Bobkov, V., Bolzonella, T., Borba, D., Borrass, K., Brambilla, M., Braun, F., Buhler, A., Carlson, A., Chankin, A., Chen, J., Chen, Y., Cirant, S., Conway, G., Coster, D., Dannert, T., Dimova, K., Drube, R., Dux, R., Eich, T., Engelhardt, K., Fahrbach, H. U., Fantz, U., Fattorini, L., Foley, M., Franzen, P., Fuchs, J. C., Gafert, J., Gal, K., Gantenbein, G., GARCA MUOZ, M., Gehre, O., Geier, A., Giannone, L., Gruber, O., Haas, G., Hartmann, D., Heger, B., Heinemann, B., Herrmann, A., Hobirk, J., Hohencker, H., Horton, L., Huart, M., Igochine, V., Jacchia, A., Jakobi, M., Jenko, F., Kallenbach, A., Klvin, S., Kardaun, O., Kaufmann, M., Keller, A., Kendl, A., Kick, M., Kim, J. W., Kirov, K., Klose, S., Kochergov, R., Kocsis, G., Kollotzek, H., Konz, C., Kraus, W., Krieger, K., KURKI SUONIO, T., Kurzan, B., Lackner, K., Lang, P. T., Lauber, P., Laux, M., Leuterer, F., Likonen, J., Lohs, A., Lorenz, A., Lorenzini, R., Lyssoivan, A., Maggi, C., Maier, H., Mank, K., Manini, A., Manso, M. E., Mantica, P., Maraschek, M., Martin, Piero, Mast, K. F., Mayer, M., Mccarthy, P., Meyer, H., Meisel, D., Meister, H., Menmuir, S., Meo, F., Merkel, P., Merkel, R., Merkl, D., Mertens, V., Monaco, F., Mck, A., Mller, H. W., Mnich, M., Murmann, H., Y. S., Na, Narayanan, R., Neu, G., Neu, R., Neuhauser, J., Nishijima, D., Nishimura, Y., Noterdaeme, J. M., Nunes, I., PACCO DCHS, M., Pautasso, G., Peeters, A. G., Pereverzev, G., Pinches, S., Poli, E., POSTHUMUS WOLFRUM, E., Ptterich, T., Pugno, R., Quigley, E., Radivojevic, I., Raupp, G., Reich, M., Riedl, R., Ribeiro, T., Rohde, V., Roth, J., Ryter, F., Saarelma, S., Sandmann, W., Santos, J., Schall, G., Schilling, H. B., Schirmer, J., Schneider, W., Schramm, G., Schweinzer, J., Schweizer, S., Scott, B., Seidel, U., Serra, F., Sihler, C., Silva, A., Sips, A., Speth, E., Stbler, A., Steuer, K. H., Stober, J., Streibl, B., Strintzi, D., Strumberger, E., Suttrop, W., Tardini, G., Tichmann, C., Treutterer, W., Troppmann, M., Tsalas, M., Urano, H., and Varela, P.

Published
2005

36. Recent ECRH results in ASDEX Upgrade

Author

Leuterer F., Dux R., Gantenbein G., Goodman T., Hobirk J., Imbeaux F., Kirov K., Mantica P., Maraschek M., Mück A., Neu R., Peeters A.G., Pereverzev G., Ryter F., Stober J., Suttrop W., Tardini G., Westerhof E., Zohm H., and AUG Team

Subjects
___
Abstract

___

Published
2003
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38. Dependence of particle transport on the heating profile in ASDEX Upgrade

Author

Stober, J., Dux, R., Gruber, O., Horton, L., Maggi, C., Meo, F., Neu, R., Noterdaeme, J., Lang, P., Lorenzini, R., Peeters, A., Pereverzev, G., Ryter, F., Sips, A., Stäbler, A., Zohm, H., and ASDEX Upgrade Team

Subjects
Physics::Plasma Physics
Abstract

The slow peaking of the density profile for high densities with moderate NBI and its disappearance with central ICRH have been reported at the last IAEA conference in Sorrento. Meanwhile a modell asumming D = 0.1 - - 0.15 χeff and the Ware-pinch has been used successfully to describe the data. Independently we have proven that the peaking is not due to differences of particle fuelling, since off-axis ICRH also leads to peaked density profiles. With the modification of treating the neoclassical ion-heat-flux separately the model holds also for discharges with lower plasma current and even for the density decay after pellet fuelling. The model is also related to the ECRH density pump-out. The separation of electron and ion chanel at low densities will be addressed. Central heating also increases the anomalous diffusivity of impurity ions which is beneficial for a fusion rector. Also Neoclassical Tearing Modes are more stable with central heating due to the flattening of the density profiles in accordance with the theoretical predictions for the dependence of the bootstrap current on the density gradient.

Published
2003

40. 'Current Holes' at ASDEX Upgrade

Author

Merkl, D., Hobirk, J., McCarthy, P., Giannone, L., Gruber, O., Igochine, V., Maraschek, M., Pereverzev, G., Schneider, W., Sips, A., Strumberger, E., and ASDEX Upgrade Team

Published
2003

46. Overview of ASDEX Upgrade results

Author

Stroth, U, Adamek, J, Aho Mantila, L, Akaslompolo, S, Amdor, C, Angioni, C, Balden, M, Bardin, S, Orte, L, Behler, K, Belonohy, E, Bergmann, A, Bernert, M, Bilato, R, Birkenmeier, G, Bobkov, V, Boom, J, Bottereau, C, Bottino, A, Braun, F, Brezinsek, S, Brochard, T, Bruedgam, M, Buhler, A, Burckhart, A, Casson, F, Chankin, A, Chapman, I, Clairet, F, Classen, I, Coenen, J, Conway, G, Coster, D, Curran, D, da Silva, F, de Marne, P, D'Inca, R, Douai, D, Drube, R, Dunne, M, Dux, R, Eich, T, Eixenberger, H, Endstrasser, N, Engelhardt, K, Esposito, B, Fable, E, Fischer, R, Fuenfgelder, H, Fuchs, J, Gal, K, Munoz, M, Geiger, B, Giannone, L, Goerler, T, da Graca, S, Greuner, H, Gruber, O, Gude, A, Guimarais, L, Guenter, S, Haas, G, Hakola, A, Hangan, D, Happel, T, Haertl, T, Hauff, T, Heinemann, B, Herrmann, A, Hobirk, J, Hoehnle, H, Hoelzl, M, Hopf, C, Houben, A, Igochine, V, Ionita, C, Janzer, A, Jenko, F, Kantor, M, Kaesemann, C, Kallenbach, A, Kalvin, S, Kappatou, A, Kardaun, O, Kasparek, W, Kaufmann, M, Kirk, A, Klingshirn, H, Kocan, M, Kocsis, G, Konz, C, Koslowski, R, Krieger, K, Kubic, M, Kurki Suonio, T, Kurzan, B, Lackner, K, Lang, P, Lauber, P, Laux, M, Lazaros, A, Leipold, F, Leuterer, F, Lindig, S, Lisgo, S, Lohs, A, Lunt, T, Maier, H, Makkonen, T, Mank, K, Manso, M, Maraschek, M, Mayer, M, Mccarthy, P, Mcdermott, R, Mehlmann, F, Meister, H, Menchero, L, Meo, F, Merkel, P, Merkel, R, Mertens, V, Merz, F, Mlynek, A, Monaco, F, Mueller, S, Mueller, H, Muenich, M, Neu, G, Neu, R, Neuwirth, D, Nocente, M, Nold, B, Noterdaeme, J, Pautasso, G, Pereverzev, G, Ploeckl, B, Podoba, Y, Pompon, F, Poli, E, Polozhiy, K, Potzel, S, Pueschel, M, Puetterich, T, Rathgeber, S, Raupp, G, Reich, M, Reimold, F, Ribeiro, T, Riedl, R, Rohde, V, Rooij, G, Roth, J, Rott, M, Ryter, F, Salewski, M, Santos, J, Sauter, P, Scarabosio, A, Schall, G, Schmid, K, Schneider, P, Schneider, W, Schrittwieser, R, Schubert, M, Schweinzer, J, Scott, B, Sempf, M, Sertoli, M, Siccinio, M, Sieglin, B, Sigalov, A, Silva, A, Sommer, F, Staebler, A, Stober, J, Streibl, B, Strumberger, E, Sugiyama, K, Suttrop, W, Tala, T, Tardini, G, Teschke, M, Tichmann, C, Told, D, Treutterer, W, Tsalas, M, Van Zeeland, M, Varela, P, Veres, G, Vicente, J, Vianello, N, Vierle, T, Viezzer, E, Viola, B, Vorpahl, C, Wachowski, M, Wagner, D, Wauters, T, Weller, A, Wenninger, R, Wieland, B, Willensdorfer, M, Wischmeier, M, Wolfrum, E, Wuersching, E, Yu, Q, Zammuto, I, Zasche, D, Zehetbauer, T, Zhang, Y, Zilker, M, Zohm, H, McCarthy, P, McDermott, R, Zohm, H., NOCENTE, MASSIMO, Stroth, U, Adamek, J, Aho Mantila, L, Akaslompolo, S, Amdor, C, Angioni, C, Balden, M, Bardin, S, Orte, L, Behler, K, Belonohy, E, Bergmann, A, Bernert, M, Bilato, R, Birkenmeier, G, Bobkov, V, Boom, J, Bottereau, C, Bottino, A, Braun, F, Brezinsek, S, Brochard, T, Bruedgam, M, Buhler, A, Burckhart, A, Casson, F, Chankin, A, Chapman, I, Clairet, F, Classen, I, Coenen, J, Conway, G, Coster, D, Curran, D, da Silva, F, de Marne, P, D'Inca, R, Douai, D, Drube, R, Dunne, M, Dux, R, Eich, T, Eixenberger, H, Endstrasser, N, Engelhardt, K, Esposito, B, Fable, E, Fischer, R, Fuenfgelder, H, Fuchs, J, Gal, K, Munoz, M, Geiger, B, Giannone, L, Goerler, T, da Graca, S, Greuner, H, Gruber, O, Gude, A, Guimarais, L, Guenter, S, Haas, G, Hakola, A, Hangan, D, Happel, T, Haertl, T, Hauff, T, Heinemann, B, Herrmann, A, Hobirk, J, Hoehnle, H, Hoelzl, M, Hopf, C, Houben, A, Igochine, V, Ionita, C, Janzer, A, Jenko, F, Kantor, M, Kaesemann, C, Kallenbach, A, Kalvin, S, Kappatou, A, Kardaun, O, Kasparek, W, Kaufmann, M, Kirk, A, Klingshirn, H, Kocan, M, Kocsis, G, Konz, C, Koslowski, R, Krieger, K, Kubic, M, Kurki Suonio, T, Kurzan, B, Lackner, K, Lang, P, Lauber, P, Laux, M, Lazaros, A, Leipold, F, Leuterer, F, Lindig, S, Lisgo, S, Lohs, A, Lunt, T, Maier, H, Makkonen, T, Mank, K, Manso, M, Maraschek, M, Mayer, M, Mccarthy, P, Mcdermott, R, Mehlmann, F, Meister, H, Menchero, L, Meo, F, Merkel, P, Merkel, R, Mertens, V, Merz, F, Mlynek, A, Monaco, F, Mueller, S, Mueller, H, Muenich, M, Neu, G, Neu, R, Neuwirth, D, Nocente, M, Nold, B, Noterdaeme, J, Pautasso, G, Pereverzev, G, Ploeckl, B, Podoba, Y, Pompon, F, Poli, E, Polozhiy, K, Potzel, S, Pueschel, M, Puetterich, T, Rathgeber, S, Raupp, G, Reich, M, Reimold, F, Ribeiro, T, Riedl, R, Rohde, V, Rooij, G, Roth, J, Rott, M, Ryter, F, Salewski, M, Santos, J, Sauter, P, Scarabosio, A, Schall, G, Schmid, K, Schneider, P, Schneider, W, Schrittwieser, R, Schubert, M, Schweinzer, J, Scott, B, Sempf, M, Sertoli, M, Siccinio, M, Sieglin, B, Sigalov, A, Silva, A, Sommer, F, Staebler, A, Stober, J, Streibl, B, Strumberger, E, Sugiyama, K, Suttrop, W, Tala, T, Tardini, G, Teschke, M, Tichmann, C, Told, D, Treutterer, W, Tsalas, M, Van Zeeland, M, Varela, P, Veres, G, Vicente, J, Vianello, N, Vierle, T, Viezzer, E, Viola, B, Vorpahl, C, Wachowski, M, Wagner, D, Wauters, T, Weller, A, Wenninger, R, Wieland, B, Willensdorfer, M, Wischmeier, M, Wolfrum, E, Wuersching, E, Yu, Q, Zammuto, I, Zasche, D, Zehetbauer, T, Zhang, Y, Zilker, M, Zohm, H, McCarthy, P, McDermott, R, Zohm, H., and NOCENTE, MASSIMO

Abstract

The medium size divertor tokamak ASDEX Upgrade (major and minor radii 1.65 m and 0.5 m, respectively, magnetic-field strength 2.5 T) possesses flexible shaping and versatile heating and current drive systems. Recently the technical capabilities were extended by increasing the electron cyclotron resonance heating (ECRH) power, by installing 2 × 8 internal magnetic perturbation coils, and by improving the ion cyclotron range of frequency compatibility with the tungsten wall. With the perturbation coils, reliable suppression of large type-I edge localized modes (ELMs) could be demonstrated in a wide operational window, which opens up above a critical plasma pedestal density. The pellet fuelling efficiency was observed to increase which gives access to H-mode discharges with peaked density profiles at line densities clearly exceeding the empirical Greenwald limit. Owing to the increased ECRH power of 4 MW, H-mode discharges could be studied in regimes with dominant electron heating and low plasma rotation velocities, i.e. under conditions particularly relevant for ITER. The ion-pressure gradient and the neoclassical radial electric field emerge as key parameters for the transition. Using the total simultaneously available heating power of 23 MW, high performance discharges have been carried out where feed-back controlled radiative cooling in the core and the divertor allowed the divertor peak power loads to be maintained below 5 MW m -2. Under attached divertor conditions, a multi-device scaling expression for the power-decay length was obtained which is independent of major radius and decreases with magnetic field resulting in a decay length of 1 mm for ITER. At higher densities and under partially detached conditions, however, a broadening of the decay length is observed. In discharges with density ramps up to the density limit, the divertor plasma shows a complex behaviour with a localized high-density region in the inner divertor before the outer divertor detaches.

Published
2013

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