The paraxial WKB code TORBEAM (Poli, 2001) is widely used for the description of electron-cyclotron waves in fusion plasmas, retaining diffraction effects through the solution of a set of ordinary differential equations. With respect to its original form, the code has undergone significant transformations and extensions, in terms of both the physical model and the spectrum of applications. The code has been rewritten in Fortran 90 and transformed into a library, which can be called from within different (not necessarily Fortran-based) workflows. The models for both absorption and current drive have been extended, including e.g. fully-relativistic calculation of the absorption coefficient, momentum conservation in electron–electron collisions and the contribution of more than one harmonic to current drive. The code can be run also for reflectometry applications, with relativistic corrections for the electron mass. Formulas that provide the coupling between the reflected beam and the receiver have been developed. Accelerated versions of the code are available, with the reduced physics goal of inferring the location of maximum absorption (including or not the total driven current) for a given setting of the launcher mirrors. Optionally, plasma volumes within given flux surfaces and corresponding values of minimum and maximum magnetic field can be provided externally to speed up the calculation of full driven-current profiles. These can be employed in real-time control algorithms or for fast data analysis.

VL - 225 U1 -FP

U2 -IMM

U5 - 0a1c01a94caffb41c92a033957ecb032 ER - TY - JOUR T1 - Non-Maxwellian fast particle effects in gyrokinetic GENE simulations JF - Physics of Plasmas Y1 - 2018 A1 - Di Siena, A. A1 - Gorler, T. A1 - Doerk, H. A1 - Bilato, R. A1 - Citrin, J. A1 - Johnson, T. A1 - Schneider, M. A1 - Poli, E. A1 - JET Contributors AB -Fast ions have recently been found to significantly impact and partially suppress plasma turbulence both in experimental and numerical studies in a number of scenarios. Understanding the underlying physics and identifying the range of their beneficial effect is an essential task for future fusion reactors, where highly energetic ions are generated through fusion reactions and external heating schemes. However, in many of the gyrokinetic codes fast ions are, for simplicity, treated as equivalent-Maxwellian-distributed particle species, although it is well known that to rigorously model highly non-thermalised particles, a non-Maxwellian background distribution function is needed. To study the impact of this assumption, the gyrokinetic code GENE has recently been extended to support arbitrary background distribution functions which might be either analytical, e.g., slowing down and bi-Maxwellian, or obtained from numerical fast ion models. A particular JET plasma with strong fast-ion related turbulence suppression is revised with these new code capabilities both with linear and nonlinear gyrokinetic simulations. It appears that the fast ion stabilization tends to be less strong but still substantial with more realistic distributions, and this improves the quantitative power balance agreement with experiments.

VL - 25 UR - https://arxiv.org/abs/1802.04561 IS - 4 U1 -FP

U2 -IMT

U5 - 11b445a4af8c06819215a9cc1c28cdad ER - TY - JOUR T1 - Analysis of electron cyclotron emission with extended electron cyclotron forward modeling JF - Plasma Physics and Controlled Fusion Y1 - 2018 A1 - Denk, S. S. A1 - Fischer, R. A1 - Smith, H. M. A1 - Helander, P. A1 - Maj, O. A1 - Poli, E. A1 - Stober, J. A1 - Stroth, U. A1 - Suttrop, W. A1 - Westerhof, E. A1 - Willensdorfer, M. VL - 60 IS - 10 U1 - FP U2 - IMM U5 - df59365cf1fee065f44d3cc4dc8ce8d2 ER - TY - JOUR T1 - Radiation transport modelling for the interpretation of oblique ECE measurements JF - EPJ Web of Conferences Y1 - 2017 A1 - Denk, S. S. A1 - Fischer, R. A1 - Maj, O. A1 - Poli, E. A1 - Stober, J. K. A1 - Stroth, U. A1 - Vanovac, B. A1 - Suttrop, W. A1 - Willensdorfer, M. A1 - ASDEX Upgrade Team AB - The electron cyclotron emission (ECE) diagnostic provides routinely electron temperature (Te) measurements. At ASDEX Upgrade an electron cyclotron forward model, solving the radiation transport equation for given Te and electron density profile, is used in the framework of integrated data analysis. With this method Te profiles can be obtained from ECE measurements even for plasmas with low optical depth. However, due to the assumption of straight lines of sight and an absorption coefficient in the quasi-perpendicular approximation this forward model is not suitable for the interpretation of measurements by ECE diagnostics with an oblique line of sight. Since radiation transport modelling is required for the interpretation of oblique ECE diagnostics we present in this paper an extended forward model that supports oblique lines of sight. To account for the refraction of the line of sight, ray tracing in the cold plasma approximation was added to the model. Furthermore, an absorption coefficient valid for arbitrary propagation was implemented. Using the revised model it is shown that for the oblique ECE Imaging diagnostic at ASDEX Upgrade there can be a significant difference between the cold resonance position and the point from which most of the observed radiation originates. VL - 147 U1 - FP U2 - IMT U5 - 1251a6e9fed6d8ff8ef5cbbc8558b67d ER - TY - CONF T1 - Non-Maxwellian background effects in gyrokinetic simulations with GENE T2 - Journal of Physics: Conference Series Y1 - 2016 A1 - Di Siena, A. A1 - Gorler, T. A1 - Doerk, H. A1 - Citrin, J. A1 - Johnson, T. A1 - Schneider, M. A1 - Poli, E. A1 - JET Contributors AB - The interaction between fast particles and core turbulence has been established as a central issue for a tokamak reactor. Recent results predict significant enhancement of electromagnetic stabilisation of ITG turbulence in the presence of fast ions. However, most of these simulations were performed with the assumption of equivalent Maxwellian distributed particles, whereas to rigorously model fast ions, a non-Maxwellian background distribution function is needed. To this aim, the underlying equations in the gyrokinetic code GENE have been re-derived and implemented for a completely general background distribution function. After verification studies, a previous investigation on a particular JET plasma has been revised with linear simulations. The plasma is composed by Deuterium, electron, Carbon impurities, NBI fast Deuterium and ICRH 3 He. Fast particle distributions have been modelled with a number of different analytic choices in order to study the impact of non-Maxwellian distributions on the plasma turbulence: slowing down and anisotropic Maxwellian. Linear growth rates are studied as a function of the wave number and compared with those obtained using an equivalent Maxwellian. Generally, the choice of the 3 He distribution seems to have a stronger impact on the microinstabilities than that of the fast Deuterium. JF - Journal of Physics: Conference Series VL - 775 IS - 1 U1 - FP U2 - IMT U3 - FP120 U5 - 615b48402fe85900d67891c750171d82 ER - TY - JOUR T1 - Status of Europe’s contribution to the ITER EC system JF - EPJ Web of Conferences Y1 - 2015 A1 - Albajar, F. A1 - Aiello, G. A1 - Alberti, S. A1 - Arnold, F. A1 - Avramidis, K. A1 - Bader, M. A1 - Batista, R. A1 - Bertizzolo, R. A1 - Bonicelli, T. A1 - Braunmueller, F. A1 - Brescan, C. A1 - Bruschi, A. A1 - von Burg, B. A1 - Camino, K. A1 - Carannante, G. A1 - Casarin, V. A1 - Castillo, A. A1 - Cauvard, F. A1 - Cavalieri, C. A1 - Cavinato, M. A1 - Chavan, R. A1 - Chelis, J. A1 - Cismondi, F. A1 - Combescure, D. A1 - Darbos, C. A1 - Farina, D. A1 - Fasel, D. A1 - Figini, L. A1 - Gagliardi, M. A1 - Gandini, F. A1 - Gantenbein, G. A1 - Gassmann, T. A1 - Gessner, R. A1 - Goodman, T. P. A1 - V. Gracia A1 - Grossetti, G. A1 - Heemskerk, C. A1 - Henderson, M. A1 - Hermann, V. A1 - Hogge, J. P. A1 - Illy, S. A1 - Ioannidis, Z. A1 - Jelonnek, J. A1 - Jin, J. A1 - Kasparek, W. A1 - Koning, J. A1 - Krause, A. S. A1 - Landis, J. D. A1 - Latsas, G. A1 - Li, F. A1 - Mazzocchi, F. A1 - Meier, A. A1 - Moro, A. A1 - Nousiainen, R. A1 - Purohit, D. A1 - Nowak, S. A1 - Omori, T. A1 - van Oosterhout, J. A1 - Pacheco, J. A1 - Pagonakis, I. A1 - Platania, P. A1 - Poli, E. A1 - Preis, A. K. A1 - Ronden, D. A1 - Rozier, Y. A1 - Rzesnicki, T. A1 - Saibene, G. A1 - Sanchez, F. A1 - Sartori, F. A1 - Sauter, O. A1 - Scherer, T. A1 - Schlatter, C. A1 - Schreck, S. A1 - Serikov, A. A1 - Siravo, U. A1 - Sozzi, C. A1 - Spaeh, P. A1 - Spichiger, A. A1 - Strauss, D. A1 - Takahashi, K. A1 - Thumm, M. A1 - Tigelis, I. A1 - Vaccaro, A. A1 - Vomvoridis, J. A1 - Tran, M. Q. A1 - Weinhorst, B. VL - 87 U1 - FP U2 - TP U5 - d2a73ecb85ae59ed760d90d206a922bd ER - TY - JOUR T1 - The European Integrated Tokamak Modelling (ITM) effort: achievements and first physics results JF - Nuclear Fusion Y1 - 2014 A1 - G.L. Falchetto A1 - Coster, D. A1 - Coelho, R. A1 - Scott, B. D. A1 - Figini, L. A1 - Kalupin, D. A1 - Nardon, E. A1 - Nowak, S. A1 - L.L. Alves A1 - Artaud, J. F. A1 - Basiuk, V. A1 - João P.S. Bizarro A1 - C. Boulbe A1 - Dinklage, A. A1 - Farina, D. A1 - B. Faugeras A1 - Ferreira, J. A1 - Figueiredo, A. A1 - Huynh, P. A1 - Imbeaux, F. A1 - Ivanova-Stanik, I. A1 - Jonsson, T. A1 - H.-J. Klingshirn A1 - Konz, C. A1 - Kus, A. A1 - Marushchenko, N. B. A1 - Pereverzev, G. A1 - M. Owsiak A1 - Poli, E. A1 - Peysson, Y. A1 - R. Reimer A1 - Signoret, J. A1 - Sauter, O. A1 - Stankiewicz, R. A1 - Strand, P. A1 - Voitsekhovitch, I. A1 - Westerhof, E. A1 - T. Zok A1 - Zwingmann, W. A1 - ITM-TF contributors A1 - ASDEX Upgrade Team A1 - JET-EFDA Contributors AB -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 edge MHD stability 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.

VL - 54 IS - 4 U1 -FP

U2 -CPP-HT

U5 - 79e32afeb1215e937326ec32033bdf01 ER - TY - JOUR T1 - Progress of the ECRH Upper Launcher design for ITER JF - Fusion Engineering and Design Y1 - 2014 A1 - Strauss, D. A1 - Aiello, G. A1 - Bruschi, A. A1 - Chavan, R. A1 - Farina, D. A1 - Figini, L. A1 - Gagliardi, M. A1 - V. Gracia A1 - Goodman, T. P. A1 - Grossetti, G. A1 - Heemskerk, C. A1 - Henderson, M. A. A1 - Kasparek, W. A1 - Krause, A. A1 - Landis, J. D. A1 - Meier, A. A1 - Moro, A. A1 - Platania, P. A1 - Plaum, B. A1 - Poli, E. A1 - Ronden, D. A1 - Saibene, G. A1 - Sanchez, F. A1 - Sauter, O. A1 - Scherer, T. A1 - Schreck, S. A1 - Serikov, A. A1 - Sozzi, C. A1 - Spaeh, P. A1 - Vaccaro, A. A1 - Weinhorst, B. KW - Blanket KW - Diamond windows KW - ECRH KW - Front steering KW - ITER KW - launcher AB - The design of the ITER ECRH system provides 20 MW millimeter wave power for central plasma heating and MHD stabilization. The system consists of an array of 24 gyrotrons with power supplies coupled to a set of transmission lines guiding the beams to the four upper and the equatorial launcher. The front steering upper launcher design described herein has passed successfully the preliminary design review, and it is presently in the final design stage. The launcher consists of a millimeter wave system and steering mechanism with neutron shielding integrated into an upper port plug with the plasma facing blanket shield module (in-vessel) and a set of ex-vessel waveguides connecting the launcher to the transmission lines. Part of the transmission lines are the ultra-low loss CVD torus diamond windows and a shutter valve, a miter bend section and the feedthroughs integrated in the plug closure plate. These components are connected by corrugated waveguides and form together the first confinement system (FCS). In-vessel, the millimeter-wave system includes a quasi-optical beam propagation system including four mirror sets and a front steering mirror. The millimeter wave system is integrated into a specifically optimized upper port plug providing structural stability to withstand plasma disruption forces and the high heat load from the plasma side with a dedicated blanket shield module. A recent update in the ITER interface definition has resulted in the recession of the upper port plug first wall panels, which is now integrated into the design. Apart from the millimeter wave system the upper port plug houses also a set of shield blocks which provide neutron shielding. An overview of the actual ITER ECRH Upper Launcher is given together with some highlights of the design. VL - 89 IS - 7-8 U1 - FP U2 - TP U5 - 65ec0341278cd5ae646408568fef03be ER - TY - JOUR T1 - Overview of ASDEX Upgrade results JF - Nuclear Fusion Y1 - 2013 A1 - Stroth, U. A1 - Adamek, J. A1 - Aho-Mantila, L. A1 - Akaslompolo, S. A1 - Amdor, C. A1 - Angioni, C. A1 - Balden, M. A1 - Bardin, S. A1 - L. Barrera Orte A1 - Behler, K. A1 - Belonohy, E. A1 - Bergmann, A. A1 - Bernert, M. A1 - Bilato, R. A1 - Birkenmeier, G. A1 - Bobkov, V. A1 - Boom, J. A1 - Bottereau, C. A1 - Bottino, A. A1 - Braun, F. A1 - Brezinsek, S. A1 - Brochard, T. A1 - M. Brüdgam A1 - Buhler, A. A1 - Burckhart, A. A1 - Casson, F. J. A1 - Chankin, A. A1 - Chapman, I. A1 - Clairet, F. A1 - Classen, I.G.J. A1 - Coenen, J. W. A1 - Conway, G. D. A1 - Coster, D. P. A1 - Curran, D. A1 - da Silva, F. A1 - P. de Marné A1 - D'Inca, R. A1 - Douai, D. A1 - Drube, R. A1 - Dunne, M. A1 - Dux, R. A1 - Eich, T. A1 - Eixenberger, H. A1 - Endstrasser, N. A1 - Engelhardt, K. A1 - Esposito, B. A1 - Fable, E. A1 - Fischer, R. A1 - H. Fünfgelder A1 - Fuchs, J. C. A1 - K. Gál A1 - M. García Muñoz A1 - Geiger, B. A1 - Giannone, L. A1 - T. Görler A1 - da Graca, S. A1 - Greuner, H. A1 - Gruber, O. A1 - Gude, A. A1 - Guimarais, L. A1 - S. Günter A1 - Haas, G. A1 - Hakola, A. H. A1 - Hangan, D. A1 - Happel, T. A1 - T. Härtl A1 - Hauff, T. A1 - Heinemann, B. A1 - Herrmann, A. A1 - Hobirk, J. A1 - H. Höhnle A1 - M. Hölzl A1 - Hopf, C. A1 - Houben, A. A1 - Igochine, V. A1 - Ionita, C. A1 - Janzer, A. A1 - Jenko, F. A1 - Kantor, M. A1 - C.-P. Käsemann A1 - Kallenbach, A. A1 - S. Kálvin A1 - Kantor, M. A1 - Kappatou, A. A1 - Kardaun, O. A1 - Kasparek, W. A1 - Kaufmann, M. A1 - Kirk, A. A1 - H.-J. Klingshirn A1 - Kocan, M. A1 - Kocsis, G. A1 - Konz, C. A1 - Koslowski, R. A1 - Krieger, K. A1 - Kubic, M. A1 - Kurki-Suonio, T. A1 - Kurzan, B. A1 - Lackner, K. A1 - Lang, P. T. A1 - Lauber, P. A1 - Laux, M. A1 - Lazaros, A. A1 - Leipold, F. A1 - Leuterer, F. A1 - Lindig, S. A1 - Lisgo, S. A1 - Lohs, A. A1 - Lunt, T. A1 - Maier, H. A1 - Makkonen, T. A1 - Mank, K. A1 - M.-E. Manso A1 - Maraschek, M. A1 - Mayer, M. A1 - McCarthy, P. J. A1 - McDermott, R. A1 - Mehlmann, F. A1 - Meister, H. A1 - Menchero, L. A1 - Meo, F. A1 - Merkel, P. A1 - Merkel, R. A1 - Mertens, V. A1 - Merz, F. A1 - Mlynek, A. A1 - Monaco, F. A1 - Müller, S. A1 - H.W. Müller A1 - M. Münich A1 - Neu, G. A1 - Neu, R. A1 - Neuwirth, D. A1 - Nocente, M. A1 - Nold, B. A1 - Noterdaeme, J. M. A1 - Pautasso, G. A1 - Pereverzev, G. A1 - B. Plöckl A1 - Podoba, Y. A1 - Pompon, F. A1 - Poli, E. A1 - Polozhiy, K. A1 - Potzel, S. A1 - Puschel, M. J. A1 - Putterich, T. A1 - Rathgeber, S. K. A1 - Raupp, G. A1 - Reich, M. A1 - Reimold, F. A1 - Ribeiro, T. A1 - Riedl, R. A1 - Rohde, V. A1 - G. J. van Rooij A1 - Roth, J. A1 - Rott, M. A1 - Ryter, F. A1 - Salewski, M. A1 - Santos, J. A1 - Sauter, P. A1 - Scarabosio, A. A1 - Schall, G. A1 - Schmid, K. A1 - Schneider, P. A. A1 - Schneider, W. A1 - Schrittwieser, R. A1 - Schubert, M. A1 - Schweinzer, J. A1 - Scott, B. A1 - Sempf, M. A1 - Sertoli, M. A1 - Siccinio, M. A1 - Sieglin, B. A1 - Sigalov, A. A1 - Silva, A. A1 - Sommer, F. A1 - A. Stäbler A1 - Stober, J. A1 - Streibl, B. A1 - Strumberger, E. A1 - Sugiyama, K. A1 - Suttrop, W. A1 - Tala, T. A1 - Tardini, G. A1 - Teschke, M. A1 - Tichmann, C. A1 - Told, D. A1 - Treutterer, W. A1 - Tsalas, M. A1 - VanZeeland, M. A. A1 - Varela, P. A1 - Veres, G. A1 - Vicente, J. A1 - Vianello, N. A1 - Vierle, T. A1 - Viezzer, E. A1 - Viola, B. A1 - Vorpahl, C. A1 - Wachowski, M. A1 - Wagner, D. A1 - Wauters, T. A1 - Weller, A. A1 - Wenninger, R. A1 - Wieland, B. A1 - Willensdorfer, M. A1 - Wischmeier, M. A1 - Wolfrum, E. A1 - E. Würsching A1 - Yu, Q. A1 - Zammuto, I. A1 - Zasche, D. A1 - Zehetbauer, T. A1 - Zhang, Y. A1 - Zilker, M. A1 - Zohm, H. AB - 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. Turbulent transport is studied in the core and the scrape-off layer (SOL). Discharges over a wide parameter range exhibit a close link between core momentum and density transport. Consistent with gyro-kinetic calculations, the density gradient at half plasma radius determines the momentum transport through residual stress and thus the central toroidal rotation. In the SOL a close comparison of probe data with a gyro-fluid code showed excellent agreement and points to the dominance of drift waves. Intermittent structures from ELMs and from turbulence are shown to have high ion temperatures even at large distances outside the separatrix. VL - 53 UR - http://hdl.handle.net/11858/00-001M-0000-0026-E166-7 IS - 10 U1 - FP U2 - PDG U5 - 0b5b08fdc590c85cc01e6d1db1958848 ER - TY - JOUR T1 - Preliminary design of the ITER ECH Upper Launcher JF - Fusion Engineering and Design Y1 - 2013 A1 - Strauss, D. A1 - Aiello, G. A1 - Chavan, R. A1 - Cirant, S. A1 - de M. Baar A1 - Farina, D. A1 - Gantenbein, G. A1 - Goodman, T. P. A1 - Henderson, M. A. A1 - Kasparek, W. A1 - Kleefeldt, K. A1 - Landis, J. D. A1 - Meier, A. A1 - Moro, A. A1 - Platania, P. A1 - Plaum, B. A1 - Poli, E. A1 - Ramponi, G. A1 - Ronden, D. A1 - Saibene, G. A1 - Sanchez, F. A1 - Sauter, O. A1 - Scherer, T. A1 - Schreck, S. A1 - Serikov, A. A1 - Sozzi, C. A1 - Spaeh, P. A1 - Vaccaro, A. A1 - Zohm, H. KW - Diamond windows KW - Electron cyclotron heating KW - ITER KW - mm-Wave optics KW - Prototyping KW - Testing AB - Abstract The design of the ITER electron cyclotron launchers recently reached the preliminary design level - the last major milestone before design finalization. The ITER ECH system contains 24 installed gyrotrons providing a maximum ECH injected power of 20 MW through transmission lines towards the tokamak. There are two EC launcher types both using a front steering mirror; one equatorial launcher (EL) for plasma heating and four upper launchers (UL) for plasma mode stabilization (neoclassical tearing modes and the sawtooth instability). A wide steering angle range of the ULs allows focusing of the beam on magnetic islands which are expected on the rational magnetic flux surfaces q = 1 (sawtooth instability), q = 3/2 and q = 2 (NTMs). In this paper the preliminary design of the ITER ECH UL is presented, including the optical system and the structural components. Highlights of the design include the torus CVD-diamond windows, the frictionless, front steering mechanism and the plasma facing blanket shield module (BSM). Numerical simulations as well as prototype tests are used to verify the design. VL - 88 UR - http://www.sciencedirect.com/science/article/pii/S0920379613003347 U1 - FP U2 - TP U5 - 7d23bc282d1dfc079da6ee58f8bd69fb ER - TY - CONF T1 - Benchmarking of electron cyclotron heating and current drive codes on ITER scenarios within the European Integrated Tokamak Modelling framework T2 - 17th Joint Workshop on Electron Cyclotron Emission and Electron Cyclotron Resonance Heating (EC-17) Y1 - 2012 A1 - Figini, L. A1 - Decker, J. A1 - Farina, D. A1 - Marushchenko, N. B. A1 - Peysson, Y. A1 - Poli, E. A1 - Westerhof, E. JF - 17th Joint Workshop on Electron Cyclotron Emission and Electron Cyclotron Resonance Heating (EC-17) PB - EDP Sciences, EPJ Web of Conferences CY - Deurne, The Netherlands VL - 32 U1 - FP U2 - CPP-HT U5 - 2d96b3f576412e42739c488c7f603026 ER - TY - JOUR T1 - Coupling the beam tracing code TORBEAM and the Fokker-Planck solver RELAX for fast electrons JF - Journal of Physics: Conference Series Y1 - 2012 A1 - Maj, O. A1 - Poli, E. A1 - Westerhof, E. AB - In this paper the interface between the beam tracing code TORBEAM [Poli, Peeters and Pereverzev, Comp. Phys. Comm. 136, 90 (2001)] and the quasi-linear Fokker-Planck solver RELAX [Westerhof, Peeters and Schippers, Rijnhuizen Report No. RR 92-211 CA, 1992] is presented together with preliminary testing results for electron cyclotron waves in ITER plasmas and their effects on the electron distribution function. The resulting numerical package allows us to account for diffraction effects in the construction of the quasi-linear wave-particle diffusion operator. The coupling of the paraxial-WKB code TORBEAM to the ray-based code RELAX requires a reinterpretation of the paraxial wave field in terms of extended rays, which are addressed in details. VL - 401 UR - http://stacks.iop.org/1742-6596/401/i=1/a=012013 U1 - FP U2 - CPP-HT U5 - d1f88ab10c4b61dac110fcbe293249a0 ER - TY - JOUR T1 - Overview of ASDEX Upgrade results JF - Nuclear Fusion Y1 - 2011 A1 - Kallenbach, A. A1 - Adamek, J. A1 - Aho-Mantila, L. A1 - Akaslompolo, S. A1 - Angioni, C. A1 - Atanasiu, C. V. A1 - Balden, M. A1 - Behler, K. A1 - Belonohy, E. A1 - Bergmann, A. A1 - Bernert, M. A1 - Bilato, R. A1 - Bobkov, V. A1 - Boom, J. A1 - Bottino, A. A1 - Braun, F. A1 - Brudgam, M. A1 - Buhler, A. A1 - Burckhart, A. A1 - Chankin, A. A1 - Classen, I.G.J. A1 - Conway, G. D. A1 - Coster, D. P. A1 - de Marne, P. A1 - D'Inca, R. A1 - Drube, R. A1 - Dux, R. A1 - Eich, T. A1 - Endstrasser, N. A1 - Engelhardt, K. A1 - Esposito, B. A1 - Fable, E. A1 - Fahrbach, H. U. A1 - Fattorini, L. A1 - Fischer, R. A1 - Flaws, A. A1 - Funfgelder, H. A1 - Fuchs, J. C. A1 - Gal, K. A1 - Munoz, M. G. A1 - Geiger, B. A1 - Adamov, M. G. A1 - Giannone, L. A1 - Giroud, C. A1 - Gorler, T. A1 - da Graca, S. A1 - Greuner, H. A1 - Gruber, O. A1 - Gude, A. A1 - Gunter, S. A1 - Haas, G. A1 - Hakola, A. H. A1 - Hangan, D. A1 - Happel, T. A1 - Hauff, T. A1 - Heinemann, B. A1 - Herrmann, A. A1 - Hicks, N. A1 - Hobirk, J. A1 - Hohnle, H. A1 - Holzl, M. A1 - Hopf, C. A1 - Horton, L. A1 - Huart, M. A1 - Igochine, V. A1 - Ionita, C. A1 - Janzer, A. A1 - Jenko, F. A1 - Kasemann, C. P. A1 - Kalvin, S. A1 - Kardaun, O. A1 - Kaufmann, M. A1 - Kirk, A. A1 - Klingshirn, H. J. A1 - Kocan, M. A1 - Kocsis, G. A1 - Kollotzek, H. A1 - Konz, C. A1 - Koslowski, R. A1 - Krieger, K. A1 - Kurki-Suonio, T. A1 - Kurzan, B. A1 - Lackner, K. A1 - Lang, P. T. A1 - Lauber, P. A1 - Laux, M. A1 - Leipold, F. A1 - Leuterer, F. A1 - Lohs, A. A1 - N C Luhmann Jr. A1 - Lunt, T. A1 - Lyssoivan, A. A1 - Maier, H. A1 - Maggi, C. A1 - Mank, K. A1 - Manso, M. E. A1 - Maraschek, M. A1 - Martin, P. A1 - Mayer, M. A1 - McCarthy, P. J. A1 - McDermott, R. A1 - Meister, H. A1 - Menchero, L. A1 - Meo, F. A1 - Merkel, P. A1 - Merkel, R. A1 - Mertens, V. A1 - Merz, F. A1 - Mlynek, A. A1 - Monaco, F. A1 - Muller, H. W. A1 - Munich, M. A1 - Murmann, H. A1 - Neu, G. A1 - Neu, R. A1 - Nold, B. A1 - Noterdaeme, J. M. A1 - Park, H. K. A1 - Pautasso, G. A1 - Pereverzev, G. A1 - Podoba, Y. A1 - Pompon, F. A1 - Poli, E. A1 - Polochiy, K. A1 - Potzel, S. A1 - Prechtl, M. A1 - Puschel, M. J. A1 - Putterich, T. A1 - Rathgeber, S. K. A1 - Raupp, G. A1 - Reich, M. A1 - Reiter, B. A1 - Ribeiro, T. A1 - Riedl, R. A1 - Rohde, V. A1 - Roth, J. A1 - Rott, M. A1 - Ryter, F. A1 - Sandmann, W. A1 - Santos, J. A1 - Sassenberg, K. A1 - Sauter, P. A1 - Scarabosio, A. A1 - Schall, G. A1 - Schmid, K. A1 - Schneider, P. A. A1 - Schneider, W. A1 - Schramm, G. A1 - Schrittwieser, R. A1 - Schweinzer, J. A1 - Scott, B. A1 - Sempf, M. A1 - Serra, F. A1 - Sertoli, M. A1 - Siccinio, M. A1 - Sigalov, A. A1 - Silva, A. A1 - Sips, A.C.C. A1 - Sommer, F. A1 - Stabler, A. A1 - Stober, J. A1 - Streibl, B. A1 - Strumberger, E. A1 - Sugiyama, K. A1 - Suttrop, W. A1 - Szepesi, T. A1 - Tardini, G. A1 - Tichmann, C. A1 - Told, D. A1 - Treutterer, W. A1 - Urso, L. A1 - Varela, P. A1 - Vincente, J. A1 - Vianello, N. A1 - Vierle, T. A1 - Viezzer, E. A1 - Vorpahl, C. A1 - Wagner, D. A1 - Weller, A. A1 - Wenninger, R. A1 - Wieland, B. A1 - Wigger, C. A1 - Willensdorfer, M. A1 - Wischmeier, M. A1 - Wolfrum, E. A1 - Wursching, E. A1 - Yadikin, D. A1 - Yu, Q. A1 - Zammuto, I. A1 - Zasche, D. A1 - Zehetbauer, T. A1 - Zhang, Y. A1 - Zilker, M. A1 - Zohm, H. KW - PHYSICS KW - REFLECTOMETRY KW - TOKAMAK AB - The ASDEX Upgrade programme is directed towards physics input to critical elements of the ITER design and the preparation of ITER operation, as well as addressing physics issues for a future DEMO design. After the finalization of the tungsten coating of the plasma facing components, the re-availability of all flywheel-generators allowed high-power operation with up to 20 MW heating power at I(p) up to 1.2 MA. Implementation of alternative ECRH schemes (140 GHz O2- and X3-mode) facilitated central heating above n(e) = 1.2 x 10(20) m(-3) and low q(95) operation at B(t) = 1.8 T. Central O2-mode heating was successfully used in high P/R discharges with 20 MW total heating power and divertor load control with nitrogen seeding. Improved energy confinement is obtained with nitrogen seeding both for type-I and type-III ELMy conditions. The main contributor is increased plasma temperature, no significant changes in the density profile have been observed. This behaviour may be explained by higher pedestal temperatures caused by ion dilution in combination with a pressure limited pedestal and hollow nitrogen profiles. Core particle transport simulations with gyrokinetic calculations have been benchmarked by dedicated discharges using variations of the ECRH deposition location. The reaction of normalized electron density gradients to variations of temperature gradients and the T(e)/T(i) ratio could be well reproduced. Doppler reflectometry studies at the L-H transition allowed the disentanglement of the interplay between the oscillatory geodesic acoustic modes, turbulent fluctuations and the mean equilibrium E x B flow in the edge negative E(r) well region just inside the separatrix. Improved pedestal diagnostics revealed also a refined picture of the pedestal transport in the fully developed H-mode type-I ELM cycle. Impurity ion transport turned out to be neoclassical in between ELMs. Electron and energy transport remain anomalous, but exhibit different recovery time scales after an ELM. After recovery of the pre-ELM profiles, strong fluctuations develop in the gradients of n(e) and T(e). The occurrence of the next ELM cannot be explained by the local current diffusion time scale, since this turns out to be too short. Fast ion losses induced by shear Alfven eigenmodes have been investigated by time-resolved energy and pitch angle measurements. This allowed the separation of the convective and diffusive loss mechanisms. VL - 51 SN - 0029-5515 IS - 9 N1 - ISI Document Delivery No.: 818DPTimes Cited: 1Cited Reference Count: 45SI U1 - FP U2 - PDG U5 - a193177a90d5b600862ca1e40bcc67af ER - TY - JOUR T1 - Overview of the ITER EC H&CD system and its capabilities JF - Fusion Engineering and Design Y1 - 2011 A1 - Omori, T. A1 - Henderson, M. A. A1 - Albajar, F. A1 - Alberti, S. A1 - Baruah, U. A1 - Bigelow, T. S. A1 - Becket, B. A1 - Bertizzolo, R. A1 - Bonicelli, T. A1 - Brusch, A. A1 - Caughman, J. B. A1 - Chavan, R. A1 - Cirant, S. A1 - Collazos, A. A1 - Cox, D. A1 - Darbos, C. A1 - M.R. de Baar A1 - Denisov, G. A1 - Farina, D. A1 - Gandini, F. A1 - Gassmann, T. A1 - Goodman, T. P. A1 - Heidinger, R. A1 - Hogge, J. P. A1 - Illy, S. A1 - Jean, O. A1 - Jin, J. A1 - Kajiwara, K. A1 - Kasparek, W. A1 - Kasugai, A. A1 - Kern, S. A1 - Kobayashi, N. A1 - Kumric, H. A1 - Landis, J. D. A1 - Moro, A. A1 - Nazare, C. A1 - Oda, Y. A1 - Pagonakis, I. A1 - Piosczyk, B. A1 - Platania, P. A1 - Plaum, B. A1 - Poli, E. A1 - Porte, L. A1 - Purohit, D. A1 - Ramponi, G. A1 - Rao, S. L. A1 - Rasmussen, D. A. A1 - Ronden, D. M. S. A1 - Rzesnicki, T. A1 - Saibene, G. A1 - Sakamoto, K. A1 - Sanchez, F. A1 - Scherer, T. A1 - Shapiro, M. A. A1 - Sozzi, C. A1 - Spaeh, P. A1 - Strauss, D. A1 - Sauter, O. A1 - Takahashi, K. A1 - Temkin, R. J. A1 - Thumm, M. A1 - Tran, M. Q. A1 - Udintsev, V.S. A1 - Zohm, H. KW - DESIGN KW - Electron Cyclotron KW - gyrotron KW - ITER KW - launcher KW - MHD stabilization AB -The Electron Cyclotron (EC) system for the ITER tokamak is designed to inject >= 20 MW RF power into the plasma for Heating and Current Drive (H&CD) applications. The EC system consists of up to 26 gyrotrons (between 1 and 2 MW each), the associated power supplies, 24 transmission lines and 5 launchers. The EC system has a diverse range of applications including central heating and current drive, current profile tailoring and control of plasma magneto-hydrodynamic (MUD) instabilities such as the sawtooth and neoclassical tearing modes (NTMs). This diverse range of applications requires the launchers to be capable of depositing the EC power across nearly the entire plasma cross section. This is achieved by two types of antennas: an equatorial port launcher (capable of injecting up to 20 MW from the plasma axis to mid-radius) and four upper port launchers providing access from inside of mid radius to near the plasma edge. The equatorial launcher design is optimized for central heating, current drive and profile tailoring, while the upper launcher should provide a very focused and peaked current density profile to control the plasma instabilities. The overall EC system has been modified during the past 3 years taking into account the issues identified in the ITER design review from 2007 and 2008 as well as integrating new technologies. This paper will review the principal objectives of the EC system, modifications made during the past 2 years and how the design is compliant with the principal objectives. (C) 2011 ITER Organization. Published by Elsevier B.V. All rights reserved.

VL - 86 SN - 0920-3796 IS - 6-8 N1 - ISI Document Delivery No.: 853KZTimes Cited: 1Cited Reference Count: 2526th Symposium on Fusion Technology (SOFT)SEP 27-OCT 01, 2010Porto, PORTUGALInst Plasmas Fusao Nucl (IPFN), Commiss European Union, Inst Soldadura Qualidade (ISQ), Fundacao Ciencia Tecnologia (FCT), Univ Tecnica Lisboa (UTL), TAP, Andante U1 -FP

U2 -TP

U5 - c370f03eff7f1a27a15a35be0d59bc06 ER - TY - Generic T1 - Conceptual design of the ECH upper launcher system for ITER Y1 - 2009 A1 - Heidinger, R. A1 - Bertizzolo, R. A1 - Bruschi, A. A1 - Chavan, R. A1 - Cirant, S. A1 - Collazos, A. A1 - de M. Baar A1 - Elzendoorn, B. A1 - Farina, D. A1 - Fischer, U. A1 - Gafert, J. A1 - Gandini, F. A1 - Gantenbein, G. A1 - Goede, A. A1 - Goodman, T. A1 - Hailfinger, G. A1 - Henderson, M. A1 - Kasparek, W. A1 - Kleefeldt, K. A1 - Landis, J. D. A1 - Meier, A. A1 - Moro, A. A1 - Platania, P. A1 - Poli, E. A1 - Ramponi, G. A1 - Saibene, G. A1 - Sanchez, F. A1 - Sauter, O. A1 - Scherer, T. A1 - Serikov, A. A1 - Shidara, H. A1 - Sozzi, C. A1 - Spaeh, P. A1 - Strauss, D. A1 - Udintsev, V.S. A1 - Vaccaro, A. A1 - Zohm, H. A1 - Zucca, C. KW - components KW - Design development KW - Electron cyclotron heating KW - Feed-back control KW - ITER KW - mm-Wave optics KW - Nuclear shielding KW - Structural AB - The challenge of developing the conceptual design of the ECH Upper Launcher system for MHD control in the ITER plasmas has been tackled by team of European Associations together with the European Domestic Agency ("F4E"). The launcher system has to meet the following requirements: (a) a mm-wave system extending from the interface to the transmission line up to the target absorption zone in the plasma and performing as an intelligent antenna; (b) a structural system integrating the mm-wave system and ensuring sufficient thermal and nuclear shielding; (C) port Plug remote handling and testing capability ensuring high Port plug system availability. The paper describes the reference launcher design. The mm-wave system is composed of waveguide and quasi-optical sections with a front steering system. An automated feedback control system is developed as a concept based on an assimilation procedure between predicted and diagnosed absorption location. The structural system consists of the blanket shield module, the port plug frame, and the internal shield for appropriate neutron shielding towards the launcher back-end. The specific advantages of a double walled structure are discussed with respect to adequate baking, to rigidity towards launcher deflection under plasma-generated loads and to removal of thermal loads, including nuclear ones. Basic Studies of remote handling (RH) to validate design development are initiated using a virtual reality simulation backed by experimental validation, for which a launcher handling test facility (LHT) is set LIP as a full scale experimental site allowing furthermore thermohydraulic studies with ITER blanket water parameters. (C) 2008 Elsevier B.V. All rights reserved. PB - Elsevier Science Sa UR -