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106 results on '"Gorelenkova M."'

1. TRANSP integrated modeling code for interpretive and predictive analysis of tokamak plasmas

Author

Pankin, A. Y, Breslau, J., Gorelenkova, M., Andre, R., Grierson, B., Sachdev, J., Goliyad, M., and Perumpilly, G.

Subjects
Physics - Plasma Physics
Abstract

This paper provides a comprehensive review of the TRANSP code, a sophisticated tool for interpretive and predictive analysis of tokamak plasmas, detailing its major capabilities and features. It describes the equations for particle, power, and momentum balance analysis, as well as the poloidal field diffusion equations. The paper outlines the spatial and time grids used in TRANSP and details the equilibrium assumptions and solvers. Various models for heating and current drive, including updates to the NUBEAM model, are discussed. The handling of large-scale events such as sawtooth crashes and pellet injections is examined, along with the predictive capabilities for advancing plasma profiles. The integration of TRANSP with the ITER Integrated Modeling and Analysis Suite (IMAS) is highlighted, demonstrating enhanced data access and analysis capabilities. Additionally, the paper discusses best practices and continuous integration techniques to enhance TRANSP's robustness. The suite of TRANSP tools, designed for efficient data analysis and simulation, further supports the optimization of tokamak operations and coupling with other tokamak codes. Continuous development and support ensure that TRANSP remains a major code for the analysis of experimental data for controlled thermonuclear fusion, maintaining its critical role in supporting the optimization of tokamak operations and advancing fusion research., Comment: Submitted to Computer Physics Communications

Published
2024

2. The hidden uncertainties in particle balance calculations and their implications for assessment of plasma performance

Author

Teplukhina, A. A., Poli, F. M., Podesta, M., Gorelenkova, M., Szepesi, G., Kazakov, Ye. O., Baranov, Y., Stancar, Z., and Contributors, the JET

Subjects
Physics - Plasma Physics
Abstract

Predictive simulations of mixed plasma discharges, like deuterium-tritium plasmas, rely on self-consistent models for particle transport. These models have to be validated with interpretive analysis of existing experiments. Accounting for uncertainties in the particle balance equation is important for modelling of mixed-plasma discharges because simulation results are directly affected by plasma composition. JET deuterium and mixed hydrogen-deuterium plasma discharges heated by neutral beams only are analysed with the TRANSP code. Influence of prescribed quantities and terms entering into the particle balance equation is quantitatively assessed on the computed plasma parameters, in particular on the neutron rate and the plasma energy. Large uncertainties in the prescribed ion temperature, plasma rotation and impurity content might result in a noticeable over- or underestimate of the computed neutron rate. A significant difference in the time evolution of the measured and computed neutron rate is observed in the interpretive simulations if same diffusivity for electrons and thermal ions is assumed. Increased thermal deuterium ion transport is required to reach agreement with the plasma composition measured at the plasma edge and the measured neutron rate. Thermal ion density computed with the particle balance equation is mostly affected by the ion outflux term.

Published
2022

3. Overview of recent physics results from MAST

Author

Kirk, A, Adamek, J, Akers, RJ, Allan, S, Appel, L, Lucini, F Arese, Barnes, M, Barrett, T, Ayed, N Ben, Boeglin, W, Bradley, J, Browning, P K, Brunner, J, Cahyna, P, Carr, M, Casson, F, Cecconello, M, Challis, C, Chapman, IT, Chapman, S, Conroy, S, Conway, N, Cooper, WA, Cox, M, Crocker, N, Crowley, B, Cardnell, S, Chorley, J, Cunningham, G, Danilov, A, Darrow, D, Dendy, R, Dickinson, D, Dorland, W, Dudson, B, Easy, L, Elmore, S, Evans, M, Farley, T, Fedorczak, N, Field, A, Fitzgerald, I, Fox, M, Freethy, S, Garzotti, L, Ghim, YC, Gi, K, Gorelenkova, M, Gracias, W, Gurl, C, Guttenfelder, W, Ham, C, Harting, D, Havlickova, E, Hawkes, N, Hender, T, Henderson, S, Hillesheim, J, Hnat, B, Horacek, J, Howard, J, Howell, D, Dunai, D, Fishpool, G, Gibson, K, Harrison, J, Highcock, E, Huang, B, Inomoto, M, Imazawa, R, Jones, O, Kadowaki, K, Kaye, S, Keeling, D, Kocan, M, Kogan, L, Komm, M, Lai, W, Leddy, J, Leggate, H, Imada, K, Klimek, I, Hollocombe, J, Lipschultz, B, Lisgo, S, Liu, YQ, Lloyd, B, Lomanowski, B, Lukin, V, Maddison, G, Madsen, J, Mailloux, J, Martin, R, McArdle, G, Lupelli, I, McClements, K, McMillan, B, Meakins, A, Meyer, H, Michael, C, Militello, F, Milnes, J, Motojima, G, Muir, D, Naylor, G, Nielsen, A, O'Brien, M, O'Mullane, M, Olsen, J, Omotani, J, Ono, Y, Pamela, S, Morris, AW, O'Gorman, T, Pangione, L, Parra, F, Patel, A, Peebles, W, Perez, R, Pinches, S, Piron, L, Price, M, Reinke, M, Ricci, P, Riva, F, Roach, C, Romanelli, M, Ryan, D, Saarelma, S, Saveliev, A, Scannell, R, Schekochihin, A, Sharapov, S, Sharples, R, Shevchenko, V, Shinohara, K, Silburn, S, Simpson, J, Stanier, A, Storrs, J, Summers, H, Takase, Y, Tamain, P, Tanabe, H, Tanaka, H, Tani, K, Taylor, D, Thomas, D, Thomas-Davies, N, Thornton, A, Turnyanskiy, M, Valovic, M, Vann, R, Van Wyk, F, Walkden, N, Watanabe, T, Wilson, H, Wischmeier, M, Yamada, T, Young, J, Zoletnik, S, Team, the MAST, and Team, the EUROfusion MST1

Subjects
Physics - Plasma Physics
Abstract

New results from MAST are presented that focus on validating models in order to extrapolate to future devices. Measurements during start-up experiments have shown how the bulk ion temperature rise scales with the square of the reconnecting field. During the current ramp up models are not able to correctly predict the current diffusion. Experiments have been performed looking at edge and core turbulence. At the edge detailed studies have revealed how filament characteristic are responsible for determining the near and far SOL density profiles. In the core the intrinsic rotation and electron scale turbulence have been measured. The role that the fast ion gradient has on redistributing fast ions through fishbone modes has led to a redesign of the neutral beam injector on MAST Upgrade. In H-mode the turbulence at the pedestal top has been shown to be consistent with being due to electron temperature gradient modes. A reconnection process appears to occur during ELMs and the number of filaments released determines the power profile at the divertor. Resonant magnetic perturbations can mitigate ELMs provided the edge peeling response is maximised and the core kink response minimised. The mitigation of intrinsic error fields with toroidal mode number n>1 has been shown to be important for plasma performance., Comment: 34 pages, 10 figures. This is an author-created, un-copyedited version of an article submitted for publication in Nuclear Fusion. IoP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from it

Published
2016
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4. Impact of interaction between RF waves and fast NBI ions on the fusion performance in JET DTE2 campaign

Author

Kirov, K. K., Challis, C. D., De la Luna, E., Eriksson, Jacob, Gallart, D., Garcia, J., Gorelenkova, M., Hobirk, J., Jacquet, P., Kappatou, A., Kazakov, Y. O., Keeling, D., King, D., Lerche, E., Maggi, C., Mailloux, J., Mantica, P., Mantsinen, M., Maslov, M., Menmuir, S., Siren, P., Stancar, Z., Van Eester, D., Kirov, K. K., Challis, C. D., De la Luna, E., Eriksson, Jacob, Gallart, D., Garcia, J., Gorelenkova, M., Hobirk, J., Jacquet, P., Kappatou, A., Kazakov, Y. O., Keeling, D., King, D., Lerche, E., Maggi, C., Mailloux, J., Mantica, P., Mantsinen, M., Maslov, M., Menmuir, S., Siren, P., Stancar, Z., and Van Eester, D.

Abstract

This work presents a study of the interaction between radio frequency (RF) waves used for ion cyclotron resonance heating and the fast deuterium (D) and tritium (T) neutral Beam injected (NBI) ions in DT plasma. The focus is on the effects of this interaction, also referred to as synergistic effects, on the fusion performance in the recent JET DTE2 campaign. Experimental data from dedicated pulses at 3.43 T/2.3 MA heated at (i) 51.4 MHz, giving the central minority H and n = 2 D, and at (ii) 32.2 MHz for the central minority 3He and n = 2 T. Resonances are analysed and conclusions are drawn and supported by modelling of the synergistic effects. Modelling with transport code TRANSP runs with and without the RF kick operator predict a moderate increase, of about 10%, in DT rates for the case of the RF wave-fast D NBI ion interactions at the n = 2 harmonic of ion cyclotron resonance, and a negligible impact due to synergistic interaction between fast T NBI ions and RF waves. JETTO modelling gives a 29% enhancement in fusion rates due to the interction between RF waves and fast D NBI ions, and an 18% enhancement in fast T NBI ions. Analysis of experimental neutron rates compared to TRANSP predictions without synergistic effects and magnetic proton recoil neutron spectrometer indicate an enhancement of approximately 25%-28% in fusion rates due to RF interaction with fast D ions, and an enhancement of approximately 5%-8% when RF waves and fast T NBI ions are interacting. The contributions of various heating and fast ion sources are assessed and discussed.

Published
2024
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5. Analysis of fusion alphas interaction with RF waves in D-T plasma at JET

Author

Kirov, K. K., Auriemma, F., Bonofiglo, P. J., Challis, C. D., De la Luna, E., Eriksson, Jacob, Gallart, D., Garcia, J., Gorelenkova, M., Hobirk, J., Jacquet, P., Kappatou, A., Kazakov, Y., Keeling, D., King, D., Kiptily, V., Lerche, E., Maggi, C., Mailloux, J., Mantica, P., Mantsinen, M., Maslov, M., Menmuir, S., Sharma, R., Siren, P., Stancar, Z., Van Eester, D., Kirov, K. K., Auriemma, F., Bonofiglo, P. J., Challis, C. D., De la Luna, E., Eriksson, Jacob, Gallart, D., Garcia, J., Gorelenkova, M., Hobirk, J., Jacquet, P., Kappatou, A., Kazakov, Y., Keeling, D., King, D., Kiptily, V., Lerche, E., Maggi, C., Mailloux, J., Mantica, P., Mantsinen, M., Maslov, M., Menmuir, S., Sharma, R., Siren, P., Stancar, Z., and Van Eester, D.

Abstract

This work studies the influence of radio frequency (RF) waves in the ion cyclotron resonance heating (ICRH) range of frequencies on fusion alphas during the recent JET D-T campaign. Fusion alphas from D-T reactions are created with energies of about 3.5 MeV and therefore have significant Doppler shifts enabling synergistic interactions between them and RF waves at a broad range of frequencies, including the ones foreseen for future fusion machines in ITER (Schneider et al 2021 Nucl. Fusion 61 126058) and SPARC (Creely et al 2020 J. Plasma Phys. 86 865860502). Resonant interactions between RF waves and alphas, also called synergistic effects, will modify the alpha distribution and ultimately will have an impact on alpha orbit losses and heating. Data from JET 3.43 T/2.3 MA pulses based on the hybrid scenario (Hobirk et al 2023 Nucl. Fusion; Hobirk et al 29th IAEA FEC23 Conf. (16-21 October 2023); Challis et al 48th EPS Conf. on Plasma Physics (27 June-1 July 2022) during the DTE2 campaign (Maggi et al 2023 Nucl. Fusion)) were used for the analysis in this study. The impact of synergistic effects on alpha orbit losses and alpha heating are assessed. The conclusions are based on the analysis of experimental data for fast alpha losses, i.e. measurements from neutral particle analyser (NPA), fast ion losses scintillator detector, Faraday cups (FCs), and TRANSP (Hawryluk et al 1980 Physics of Plasmas Close to Thermonuclear Conditions vol 1 (CEC) pp 19-46) simulations. Experimental data and TRANSP analysis indicates that there are indeed changes in the alpha distribution function (DF) due to interaction with RF waves. Data from the NPA show increased 4He flux in the range from a few hundred keV up to 800 keV for pulses with RF power, while TRANSP clearly shows modifications in the fast alpha DF for these energies. Data from the scintillator detector and the FCs were compared for pulses with and without ICRH power and versus cases with enhanced alpha losses due to MHD activ

Published
2024
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6. An overview of recent physics results from NSTX

Author

Kaye, SM, Abrams, T, Ahn, J-W, Allain, JP, Andre, R, Andruczyk, D, Barchfeld, R, Battaglia, D, Bhattacharjee, A, Bedoya, F, Bell, RE, Belova, E, Berkery, J, Berry, L, Bertelli, N, Beiersdorfer, P, Bialek, J, Bilato, R, Boedo, J, Bonoli, P, Boozer, A, Bortolon, A, Boyer, MD, Boyle, D, Brennan, D, Breslau, J, Brooks, J, Buttery, R, Capece, A, Canik, J, Chang, CS, Crocker, N, Darrow, D, Davis, W, Delgado-Aparicio, L, Diallo, A, D'Ippolito, D, Domier, C, Ebrahimi, F, Ethier, S, Evans, T, Ferraro, N, Ferron, J, Finkenthal, M, Fonck, R, Fredrickson, E, Fu, GY, Gates, D, Gerhardt, S, Glasser, A, Gorelenkov, N, Gorelenkova, M, Goumiri, I, Gray, T, Green, D, Guttenfelder, W, Harvey, R, Hassanein, A, Heidbrink, W, Hirooka, Y, Hooper, EB, Hosea, J, Humphreys, D, Jaeger, EF, Jarboe, T, Jardin, S, Jaworski, MA, Kaita, R, Kessel, C, Kim, K, Koel, B, Kolemen, E, Kramer, G, Ku, S, Kubota, S, LaHaye, RJ, Lao, L, LeBlanc, BP, Levinton, F, Liu, D, Lore, J, Lucia, M, Luhmann, N, Maingi, R, Majeski, R, Mansfield, D, Maqueda, R, McKee, G, Medley, S, Meier, E, Menard, J, Mueller, D, Munsat, T, Muscatello, C, Myra, J, Nelson, B, Nichols, J, Ono, M, Osborne, T, and Park, J-K

Subjects
NSTX, spherical torus, overview, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Fluids & Plasmas
Abstract

The National Spherical Torus Experiment (NSTX) is currently being upgraded to operate at twice the toroidal field and plasma current (up to 1T and 2MA), with a second, more tangentially aimed neutral beam (NB) for current and rotation control, allowing for pulse lengths up to 5s. Recent NSTX physics analyses have addressed topics that will allow NSTX-Upgrade to achieve the research goals critical to a Fusion Nuclear Science Facility. These include producing stable, 100% non-inductive operation in high-performance plasmas, assessing plasma-material interface (PMI) solutions to handle the high heat loads expected in the next-step devices and exploring the unique spherical torus (ST) parameter regimes to advance predictive capability. Non-inductive operation and current profile control in NSTX-U will be facilitated by co-axial helicity injection (CHI) as well as radio frequency (RF) and NB heating. CHI studies using NIMROD indicate that the reconnection process is consistent with the 2D Sweet-Parker theory. Full-wave AORSA simulations show that RF power losses in the scrape-off layer (SOL) increase significantly for both NSTX and NSTX-U when the launched waves propagate in the SOL. Toroidal Alfvén eigenmode avalanches and higher frequency Alfvén eigenmodes can affect NB-driven current through energy loss and redistribution of fast ions. The inclusion of rotation and kinetic resonances, which depend on collisionality, is necessary for predicting experimental stability thresholds of fast growing ideal wall and resistive wall modes. Neutral beams and neoclassical toroidal viscosity generated from applied 3D fields can be used as actuators to produce rotation profiles optimized for global stability. DEGAS-2 has been used to study the dependence of gas penetration on SOL temperatures and densities for the MGI system being implemented on the Upgrade for disruption mitigation. PMI studies have focused on the effect of ELMs and 3D fields on plasma detachment and heat flux handling. Simulations indicate that snowflake and impurity seeded radiative divertors are candidates for heat flux mitigation in NSTX-U. Studies of lithium evaporation on graphite surfaces indicate that lithium increases oxygen surface concentrations on graphite, and deuterium-oxygen affinity, which increases deuterium pumping and reduces recycling. In situ and test-stand experiments of lithiated graphite and molybdenum indicate temperature-enhanced sputtering, although that test-stand studies also show the potential for heat flux reduction through lithium vapour shielding. Non-linear gyro kinetic simulations have indicated that ion transport can be enhanced by a shear-flow instability, and that non-local effects are necessary to explain the observed rapid changes in plasma turbulence. Predictive simulations have shown agreement between a microtearing-based reduced transport model and the measured electron temperatures in a microtearing unstable regime. Two Alfvén eigenmode-driven fast ion transport models have been developed and successfully benchmarked against NSTX data. Upgrade construction is moving on schedule with initial physics research operation of NSTX-U planned for mid-2015.

Published
2015

7. Energetic ion transport by microturbulence is insignificant in tokamaksa)

Author

Pace, DC, Austin, ME, Bass, EM, Budny, RV, Heidbrink, WW, Hillesheim, JC, Holcomb, CT, Gorelenkova, M, Grierson, BA, McCune, DC, McKee, GR, Muscatello, CM, Park, JM, Petty, CC, Rhodes, TL, Staebler, GM, Suzuki, T, Van Zeeland, MA, Waltz, RE, Wang, G, White, AE, Yan, Z, Yuan, X, and Zhu, YB

Subjects
Astronomical and Space Sciences, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Classical Physics, Fluids & Plasmas
Abstract

Energetic ion transport due to microturbulence is investigated in magnetohydrodynamic-quiescent plasmas by way of neutral beam injection in the DIII-D tokamak [J. L. Luxon, Nucl. Fusion 42, 614 (2002)]. A range of on-axis and off-axis beam injection scenarios are employed to vary relevant parameters such as the character of the background microturbulence and the value of E b / T e, where Eb is the energetic ion energy and Te the electron temperature. In all cases, it is found that any transport enhancement due to microturbulence is too small to observe experimentally. These transport effects are modeled using numerical and analytic expectations that calculate the energetic ion diffusivity due to microturbulence. It is determined that energetic ion transport due to coherent fluctuations (e.g., Alfvén eigenmodes) is a considerably larger effect and should therefore be considered more important for ITER. © 2013 AIP Publishing LLC.

Published
2013

8. Alfvén eigenmode stability and fast ion loss in DIII-D and ITER reversed magnetic shear plasmas

Author

Van Zeeland, MA, Gorelenkov, NN, Heidbrink, WW, Kramer, GJ, Spong, DA, Austin, ME, Fisher, RK, García Muñoz, M, Gorelenkova, M, Luhmann, N, Murakami, M, Nazikian, R, Pace, DC, Park, JM, Tobias, BJ, and White, RB

Subjects
Fluids & Plasmas, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Atomic, Molecular, Nuclear, Particle and Plasma Physics
Abstract

Neutral beam injection into reversed-magnetic shear DIII-D plasmas produces a variety of Alfvénic activity including toroidicity-induced Alfvén eigenmodes (TAEs) and reversed shear Alfvén eigenmodes (RSAEs). With measured equilibrium profiles as inputs, the ideal MHD code NOVA is used to calculate eigenmodes of these plasmas. The postprocessor code NOVA-K is then used to perturbatively calculate the actual stability of the modes, including finite orbit width and finite Larmor radius effects, and reasonable agreement with the spectrum of observed modes is found. Using experimentally measured mode amplitudes, fast ion orbit following simulations have been carried out in the presence of the NOVA calculated eigenmodes and are found to reproduce the dominant energy, pitch and temporal evolution of the losses measured using a large bandwidth scintillator diagnostic. The same analysis techniques applied to a DT 8 MA ITER steady-state plasma scenario with reversed-magnetic shear and both beam ion and alpha populations show Alfvén eigenmode instability. Both RSAEs and TAEs are found to be unstable with maximum growth rates occurring for toroidal mode number n=6 and the majority of the drive coming from fast ions injected by the 1MeV negative ion beams. AE instability due to beam ion drive is confirmed by the non-perturbative code TAEFL. Initial fast ion orbit following simulations using the unstable modes with a range of amplitudes (δB/B=10 -510 -3) have been carried out and show negligible fast ion loss. The lack of fast ion loss is a result of loss boundaries being limited to large radii and significantly removed from the actual modes themselves. © 2012 IAEA, Vienna.

Published
2012

9. Fast-ion effects during test blanket module simulation experiments in DIII-D

Author

Kramer, GJ, Budny, BV, Ellis, R, Gorelenkova, M, Heidbrink, WW, Kurki-Suonio, T, Nazikian, R, Salmi, A, Schaffer, MJ, Shinohara, K, Snipes, JA, Spong, DA, Koskela, T, and Van Zeeland, MA

Subjects
Atomic, Molecular, Nuclear, Particle and Plasma Physics, Fluids & Plasmas
Abstract

Fast beam-ion losses were studied in DIII-D in the presence of a scaled mock-up of two test blanket modules (TBM) for ITER. Heating of the protective tiles on the front of the TBM surface was found when neutral beams were injected and the TBM fields were engaged. The fast-ion core confinement was not significantly affected. Different orbit-following codes predict the formation of a hot spot on the TBM surface arising from beam ions deposited near the edge of the plasma. The codes are in good agreement with each other on the total power deposited at the hot spot, predicting an increase in power with decreasing separation between the plasma edge and the TBM surface. A thermal analysis of the heat flow through the tiles shows that the simulated power can account for the measured tile temperature rise. The thermal analysis, however, is very sensitive to the details of the localization of the hot spot, which is predicted to be different among the various codes. © 2011 IAEA, Vienna.

Published
2011

10. Measurements and modeling of Alfvén eigenmode induced fast ion transport and loss in DIII-D and ASDEX Upgradea)

Author

Van Zeeland, MA, Heidbrink, WW, Fisher, RK, Muñoz, M García, Kramer, GJ, Pace, DC, White, RB, Aekaeslompolo, S, Austin, ME, Boom, JE, Classen, IGJ, da Graça, S, Geiger, B, Gorelenkova, M, Gorelenkov, NN, Hyatt, AW, Luhmann, N, Maraschek, M, McKee, GR, Moyer, RA, Muscatello, CM, Nazikian, R, Park, H, Sharapov, S, Suttrop, W, Tardini, G, Tobias, BJ, and Zhu, YB

Subjects
Astronomical and Space Sciences, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Classical Physics, Fluids & Plasmas
Abstract

Neutral beam injection into reversed magnetic shear DIII-D and ASDEX Upgrade plasmas produces a variety of Alfvénic activity including toroidicity-induced Alfvén eigenmodes and reversed shear Alfvén eigenmodes (RSAEs). These modes are studied during the discharge current ramp phase when incomplete current penetration results in a high central safety factor and increased drive due to multiple higher order resonances. Scans of injected 80 keV neutral beam power on DIII-D showed a transition from classical to AE dominated fast ion transport and, as previously found, discharges with strong AE activity exhibit a deficit in neutron emission relative to classical predictions. By keeping beam power constant and delaying injection during the current ramp, AE activity was reduced or eliminated and a significant improvement in fast ion confinement observed. Similarly, experiments in ASDEX Upgrade using early 60 keV neutral beam injection drove multiple unstable RSAEs. Periods of strong RSAE activity are accompanied by a large (peak δS n/Sn ≈ 60%) neutron deficit. Losses of beam ions modulated at AE frequencies were observed using large bandwidth energy and pitch resolving fast ion loss scintillator detectors and clearly identify their role in the process. Modeling of DIII-D loss measurements using guiding center following codes to track particles in the presence of ideal magnetohydrodynamic (MHD) calculated AE structures (validated by comparison to experiment) is able to reproduce the dominant energy, pitch, and temporal evolution of these losses. While loss of both co and counter current fast ions occurs, simulations show that the dominant loss mechanism observed is the mode induced transition of counter-passing fast ions to lost trapped orbits. Modeling also reproduces a coherent signature of AE induced losses and it was found that these coherent losses scale proportionally with the amplitude; an additional incoherent contribution scales quadratically with the mode amplitude. © 2011 American Institute of Physics.

Published
2011

11. Overview of interpretive modelling of fusion performance in JET DTE2 discharges with TRANSP

Author

Stancar, Z, Kirov, K, Auriemma, F, Kim, H, Poradzinski, M, Sharma, R, Lorenzini, R, Ghani, Z, Gorelenkova, M, Poli, F, Boboc, A, Brezinsek, S, Carvalho, P, Casson, F, Challis, C, Delabie, E, Van Eester, D, Fitzgerald, M, Fontdecaba, J, Gallart, D, Garcia, J, Garzotti, L, Giroud, C, Kappatou, A, Kazakov, Y, King, D, Kiptily, V, Kos, D, Lerche, E, Litherland-Smith, E, Maggi, C, Mantica, P, Mantsinen, M, Maslov, M, Menmuir, S, Nocente, M, Oliver, H, Sharapov, S, Sirén, P, Solano, E, Sun, H, Szepesi, G, Kirov, KK, Kim, HT, Casson, FJ, Challis, CD, Fontdecaba, JM, Kazakov, YO, King, DB, Kiptily, VG, Maggi, CF, Mantsinen, MJ, Oliver, HJC, Sharapov, SE, Solano, ER, Stancar, Z, Kirov, K, Auriemma, F, Kim, H, Poradzinski, M, Sharma, R, Lorenzini, R, Ghani, Z, Gorelenkova, M, Poli, F, Boboc, A, Brezinsek, S, Carvalho, P, Casson, F, Challis, C, Delabie, E, Van Eester, D, Fitzgerald, M, Fontdecaba, J, Gallart, D, Garcia, J, Garzotti, L, Giroud, C, Kappatou, A, Kazakov, Y, King, D, Kiptily, V, Kos, D, Lerche, E, Litherland-Smith, E, Maggi, C, Mantica, P, Mantsinen, M, Maslov, M, Menmuir, S, Nocente, M, Oliver, H, Sharapov, S, Sirén, P, Solano, E, Sun, H, Szepesi, G, Kirov, KK, Kim, HT, Casson, FJ, Challis, CD, Fontdecaba, JM, Kazakov, YO, King, DB, Kiptily, VG, Maggi, CF, Mantsinen, MJ, Oliver, HJC, Sharapov, SE, and Solano, ER

Abstract

In the paper we present an overview of interpretive modelling of a database of JET-ILW 2021 D-T discharges using the TRANSP code. The main aim is to assess our capability of computationally reproducing the fusion performance of various D-T plasma scenarios using different external heating and D-T mixtures, and to understand the performance driving mechanisms. We find that interpretive simulations confirm a general power-law relationship between increasing external heating power and fusion output, which is supported by absolutely calibrated neutron yield measurements. A comparison of measured and computed D-T neutron rates shows that the calculations' discrepancy depends on the absolute neutron yield. The calculations are found to agree well with measurements for higher performing discharges with external heating power above similar to 20 MW , while low-neutron shots display an average discrepancy of around +40% compared to measured neutron yields. A similar trend is found for the ratio between thermal and beam-target fusion, where larger discrepancies are seen in shots with dominant beam-driven performance. We compare the observations to studies of JET-ILW D discharges, to find that on average the fusion performance is well modelled over a range of heating power, although an increased unsystematic deviation for lower-performing shots is observed. The ratio between thermal and beam-induced D-T fusion is found to be increasing weakly with growing external heating power, with a maximum value of greater than or similar to 1 achieved in a baseline scenario experiment. An evaluation of the fusion power computational uncertainty shows a strong dependence on the plasma scenario type and fusion drive characteristics, varying between +/- 25% and 35%. D-T fusion alpha simulations show that the ratio between volume-integrated electron and ion heating from alphas is less than or similar to 10 for the majority of analysed discharges. Alphas are computed to contribute between simi

Published
2023

12. Impact of ICRH heating of fast D and T ions on fusion performance in JET DTE2 campaign.

Author

Kirov, K., Challis, C., Luna, E. de la, Gallart, D., Garcia, J., Gorelenkova, M., Hobirk, J., Jacquet, P., Kappatou, A., Kazakov, Y., Keeling, D., King, D., Lerche, E., Maggi, C., Mailloux, J., Mantica, M. I., Mantsinen, M., Maslov, M., Menmuir, S., and Stancar, Z.

Subjects
CYCLOTRON resonance, FAST ions, HEATING, ION sources, ION acoustic waves, PLASMA beam injection heating, PENETRATION mechanics
Abstract

This work studies the impact of the Ion Cyclotron Resonance Heating (ICRH) of the fast Neutral Beam Injected (NBI) D and T ions on the fusion performance in recent JET DTE2 campaign. The effect of the Radio Frequency (RF) wave on fast NBI D and T ion dynamics was analyzed by means of TRANSP simulations. Moderate increase, 5-10%, in DT reaction rates was predicted by TRANSP for the case of ICRH heating of fast NBI D ions at n=2 harmonic of ion cyclotron resonance. The simulations have shown that synergistic interaction between fast NBI T ions and RF waves have little or no impact on the fusion performance in the experimental conditions discussed here. Contribution of various heating and fast ion sources have been assessed and discussed. The absence of strong interaction between fast NBI T ions and RF waves was attributed to the poorer penetration of the T beams leading to lower fast T ion densities in the core and the lower perpendicular velocity of the fast NBI T ions resulting in diminished intensity of fast particle – RF wave interaction. [ABSTRACT FROM AUTHOR]

Published
2023
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13. Alfvén eigenmode stability in a JET afterglow deuterium plasma and projections to deuterium–tritium plasmas

Author

Teplukhina, A A, primary, Podestà, M, additional, Poli, F M, additional, Gorelenkova, M, additional, Bonofiglo, P J, additional, Collins, C S, additional, Dumont, R J, additional, Hawkes, N C, additional, Keeling, D L, additional, Sertoli, M, additional, Szepesi, G, additional, Thorman, A, additional, and Contributors, JET, additional

Published
2023
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14. Experimental validation of an integrated modelling approach to neutron emission studies at JET

Author

Stancar, Z, Ghani, Z, Eriksson, J, Zohar, A, Conroy, S, Kazakov, Y, Craciunescu, T, Kirov, K, Nocente, M, Garzotti, L, Radulovic, V, Siren, P, Kiptily, V, Baranov, Y, Szepesi, G, Dreval, M, Gorelenkova, M, Weisen, H, Militello-Asp, E, Snoj, L, Stancar Z., Ghani Z., Eriksson J., Zohar A., Conroy S., Kazakov Y. O., Craciunescu T., Kirov K., Nocente M., Garzotti L., Radulovic V., Siren P., Kiptily V., Baranov Y., Szepesi G., Dreval M., Gorelenkova M., Weisen H., Militello-Asp E., Snoj L., Stancar, Z, Ghani, Z, Eriksson, J, Zohar, A, Conroy, S, Kazakov, Y, Craciunescu, T, Kirov, K, Nocente, M, Garzotti, L, Radulovic, V, Siren, P, Kiptily, V, Baranov, Y, Szepesi, G, Dreval, M, Gorelenkova, M, Weisen, H, Militello-Asp, E, Snoj, L, Stancar Z., Ghani Z., Eriksson J., Zohar A., Conroy S., Kazakov Y. O., Craciunescu T., Kirov K., Nocente M., Garzotti L., Radulovic V., Siren P., Kiptily V., Baranov Y., Szepesi G., Dreval M., Gorelenkova M., Weisen H., Militello-Asp E., and Snoj L.

Abstract

An integrated modelling methodology for the calculation of realistic plasma neutron sources for the JET tokamak has been developed. The computational chain comprises TRANSP plasma transport and DRESS neutron spectrum calculations, and their coupling to the MCNP neutron transport code, bridging plasma physics and neutronics. In the paper we apply the developed methodology to the analysis of neutron emission properties of deuterium and helium plasmas at JET, and validate individual modelling steps against neutron diagnostic measurements. Two types of JET discharges are modelled-baseline-like and three-ion radio-frequency scenarios-due to their diversity in plasma heating, characteristics of the induced fast ion population, and the imprint of these on neutron emission properties. The neutron emission modelling results are quantitatively compared to the total neutron yield from fission chambers, neutron emissivity profiles from the neutron camera, neutron spectra from the time-of-flight spectrometer, and neutron activation measurements. The agreement between measured and calculated quantities is found to be satisfactory for all four diagnostic systems within the estimated experimental and computational uncertainties. Additionally, the effect of neutrons not originating from the dominating D(D, n)He-3 reactions is studied through modelling of triton burnup DT neutrons, and, in mixed D-He-3 plasmas, neutrons produced in the Be-9(D, n gamma)B-10 reaction on impurities. It is found that these reactions can contribute up to several percent to the total neutron yield and dominate the neutron activation of samples. The effect of MeV-range fast ions on the neutron activation of In-115 and Al-27 samples is measured and computationally validated.

Published
2021

15. Development of a reduced model for energetic particle transport by sawteeth in tokamaks

Author

Podesta, M., Gorelenkova, M., Gorelenkov, N. N., White, R. B., Bonofiglo, P. J., Poli, F. M., Teplukhina, A., Yang, J., Cecconello, Marco, Vallar, M., Podesta, M., Gorelenkova, M., Gorelenkov, N. N., White, R. B., Bonofiglo, P. J., Poli, F. M., Teplukhina, A., Yang, J., Cecconello, Marco, and Vallar, M.

Abstract

The sawtooth instability is known for inducing transport and loss of energetic particles (EPs), and for generating seed magnetic islands that can trigger tearing modes. Both effects degrade the overall plasma performance. Several theories and numerical models have been previously developed to quantify the expected EP transport caused by sawteeth, with various degrees of sophistication to differentiate the response of EPs at different energies and on different orbits (e.g. passing vs. trapped), although the analysis is frequently limited to a single time slice during a tokamak discharge. This work describes the development and initial benchmark of a framework that enables a reduced model for EP transport by sawteeth retaining the full EP phase-space information. The model, implemented in the ORBIT hamiltonian particle-following code, can be used either as a standalone post-processor taking input data from codes such as TRANSP, or as a pre-processor to compute transport coefficients that can be fed back to TRANSP for time-dependent simulations including the effects of sawteeth on EPs. The advantage of the latter approach is that the evolution of the EP distribution can be simulated quantitatively for sawtoothing discharges, thus enabling a more accurate modeling of sources, sinks and overall transport properties of EP and thermal plasma species for comprehensive physics studies that require detailed information of the fast-ion distribution function and its evolution over time.

Published
2022
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16. Validation of realistic Monte Carlo plasma gamma-ray source on JET discharges

Author

??ohar, A, Nocente, M, Kos, B, ??tancar, ?, Rebai, M, Rigamonti, D, Craciunescu, T, Gorelenkova, M, Kazakov, Y, Kiptily, V, Snoj, L, Tardocchi, M, Lengar, I, Contributors, J, A. ??ohar, M. Nocente, B. Kos, ??. ??tancar, M. Rebai, D. Rigamonti, T. Craciunescu, M. Gorelenkova, Ye. O. Kazakov, V. G. Kiptily, L. Snoj, M. Tardocchi, I. Lengar, JET Contributors, ??ohar, A, Nocente, M, Kos, B, ??tancar, ?, Rebai, M, Rigamonti, D, Craciunescu, T, Gorelenkova, M, Kazakov, Y, Kiptily, V, Snoj, L, Tardocchi, M, Lengar, I, Contributors, J, A. ??ohar, M. Nocente, B. Kos, ??. ??tancar, M. Rebai, D. Rigamonti, T. Craciunescu, M. Gorelenkova, Ye. O. Kazakov, V. G. Kiptily, L. Snoj, M. Tardocchi, I. Lengar, and JET Contributors

Abstract

A novel modelling methodology has been developed for the creation of a realistic plasma gamma-ray source for Monte Carlo transport simulations in the tokamak JET. The methodology couples the TRANSP code for plasma transport calculations with the MCNP Monte Carlo particle transport code, thus connecting plasma physics with gamma-ray transport. This paper presents the validation of the developed source methodology by comparing calculated gamma-ray spectra with measurements performed at JET. The validation focuses on gamma-ray spectra measured by the tangential gamma-ray spectrometer during two JET three ion RF scenario discharges, performed in the JET 2019 deuterium experimental campaign. For validation the calculated plasma gamma-ray spectrum was combined with the neutron induced prompt gamma-ray background, originating in the vacuum vessel, and scaled to absolute values calculating the total number of plasma gamma-ray and neutron emitting reactions. The comparison between calculated and measured gamma-ray spectra shows good agreement with the shape of the calculated gamma-ray spectra matching that of measurements for both studied discharges. Moreover, the calculated absolute values of the gamma-ray spectra were of the same order of magnitude at the position of the gamma-ray detector located at the end of a long line-of-sight in a biological shield. The comparison has validated the developed plasma gamma-ray source methodology for MCNP photon transport calculations at JET. The validation provides a basis for the developed plasma gamma-ray source to be used as a support for the development of future tokamaks such as DEMO.

Published
2022

19. Experimental validation of an integrated modelling approach to neutron emission studies at JET

Author

Stancar, Z., Ghani, Z., Eriksson, Johan, Zohar, A., Conroy, Sean, Kazakov, Ye O., Craciunescu, T., Kirov, K., Nocente, M., Garzotti, L., Radulovic, V, Siren, P., Kiptily, V, Baranov, Y., Szepesi, G., Dreval, M., Gorelenkova, M., Weisen, H., Militello-Asp, E., Snoj, L., Stancar, Z., Ghani, Z., Eriksson, Johan, Zohar, A., Conroy, Sean, Kazakov, Ye O., Craciunescu, T., Kirov, K., Nocente, M., Garzotti, L., Radulovic, V, Siren, P., Kiptily, V, Baranov, Y., Szepesi, G., Dreval, M., Gorelenkova, M., Weisen, H., Militello-Asp, E., and Snoj, L.

Abstract

An integrated modelling methodology for the calculation of realistic plasma neutron sources for the JET tokamak has been developed. The computational chain comprises TRANSP plasma transport and DRESS neutron spectrum calculations, and their coupling to the MCNP neutron transport code, bridging plasma physics and neutronics. In the paper we apply the developed methodology to the analysis of neutron emission properties of deuterium and helium plasmas at JET, and validate individual modelling steps against neutron diagnostic measurements. Two types of JET discharges are modelled-baseline-like and three-ion radio-frequency scenarios-due to their diversity in plasma heating, characteristics of the induced fast ion population, and the imprint of these on neutron emission properties. The neutron emission modelling results are quantitatively compared to the total neutron yield from fission chambers, neutron emissivity profiles from the neutron camera, neutron spectra from the time-of-flight spectrometer, and neutron activation measurements. The agreement between measured and calculated quantities is found to be satisfactory for all four diagnostic systems within the estimated experimental and computational uncertainties. Additionally, the effect of neutrons not originating from the dominating D(D, n)He-3 reactions is studied through modelling of triton burnup DT neutrons, and, in mixed D-He-3 plasmas, neutrons produced in the Be-9(D, n gamma)B-10 reaction on impurities. It is found that these reactions can contribute up to several percent to the total neutron yield and dominate the neutron activation of samples. The effect of MeV-range fast ions on the neutron activation of In-115 and Al-27 samples is measured and computationally validated.

Published
2021
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20. Validation of neutron emission and neutron energy spectrum calculations on a Mega Ampere Spherical Tokamak with directional relativistic spectrum simulator

Author

Sperduti, Andrea, Klimek, Iwona, Conroy, Sean, Cecconello, Marco, Gorelenkova, M., Snicker, A., Sperduti, Andrea, Klimek, Iwona, Conroy, Sean, Cecconello, Marco, Gorelenkova, M., and Snicker, A.

Abstract

The recently developed directional relativistic spectrum simulator (DRESS) code has been validated for the first time against numerical calculations and experimental measurements performed on the Mega Ampere Spherical Tokamak . In this validation, the neutron emissivities and rates computed by DRESS are benchmarked against TRANSP/NUBEAM predictions while the neutron energy spectra provided by DRESS taking as input TRANSP/NUBEAM and ASCOT/BBNBI in Gyro-Orbit mode fast ion distributions are validated against proton pulse height spectra measured by the neutron flux monitor. Excellent agreement was found between DRESS and TRANSP/NUBEAM predictions of local and total neutron emission.

Published
2021
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21. Fast ion transport by sawtooth instability in the presence of ICRF-NBI synergy in JET plasmas

Author

Teplukhina, A, Podesta, M, Poli, F, Szepesi, G, Kazakov, Y, Bonofiglo, P, Gorelenkova, M, Nocente, M, Ongena, J, Stancar, Z, Teplukhina, AA, Poli, FM, Kazakov, YO, Bonofiglo, PJ, Teplukhina, A, Podesta, M, Poli, F, Szepesi, G, Kazakov, Y, Bonofiglo, P, Gorelenkova, M, Nocente, M, Ongena, J, Stancar, Z, Teplukhina, AA, Poli, FM, Kazakov, YO, and Bonofiglo, PJ

Abstract

JET experiments have shown that the three-ion scenarios using waves in the ion cyclotron range of frequencies (ICRF) is an efficient way to build fast ion population through beam ion acceleration by radio frequency (RF) waves. Such a heating scheme is applied to plasmas with at least two thermal ion species. Analysis of mixed discharges with complex heating schemes requires a workflow that allows to model thermal and fast ion transport consistently. This paper is dedicated to modelling of a mixed plasma discharge with significant fraction of fast ions and contributes to development of fast ion transport models. For interpretive analysis with the TRANSP code a JET hydrogen-deuterium plasma discharge with neutral beam injection (NBI) and ICRF heating has been chosen. The task is complicated by NBI-ICRF synergy and plasma magnetohydrodynamic activity, like sawtooth crashes. D beam ions accelerated by RF waves form a high energy tail in fast ion distribution. Significant difference between the neutron rate computed by TRANSP and measured one is observed if the same diffusivity for electrons and ions is assumed. Sensitivity studies show that uncertainties in input plasma parameters and thermal ion transport models are crucial for modelling mixed plasma discharges and increased D transport is required to reach the plasma composition consistent with diagnostic measurements at the plasma edge. Fast ion redistribution by a sawtooth instability is characterised by non-resonant transport due to reconnection of magnetic field lines and resonant transport caused by resonance interaction between the instability and fast ions. With ORBIT simulations it has been shown that resonant interaction strongly affects fast ions of high energies, like beam ions accelerated by RF waves and fusion products. For the considered case, fast ion profiles simulated by ORBIT remain peaked after the sawtooth crashes.

Published
2021

22. Validation of realistic Monte Carlo plasma gamma-ray source on JET discharges.

Author

Žohar, A., Nocente, M., Kos, B., Štancar, Ž., Rebai, M., Rigamonti, D., Craciunescu, T., Gorelenkova, M., Kazakov, Ye.O., Kiptily, V.G., Snoj, L., Tardocchi, M., Lengar, I., and JET Contributors

Subjects
PLASMA sources, PLASMA physics, HIGH-frequency discharges, JETS (Nuclear physics), ABSOLUTE value, NEUTRON transport theory
Abstract

A novel modelling methodology has been developed for the creation of a realistic plasma gamma-ray source for Monte Carlo transport simulations in the tokamak JET. The methodology couples the TRANSP code for plasma transport calculations with the MCNP Monte Carlo particle transport code, thus connecting plasma physics with gamma-ray transport. This paper presents the validation of the developed source methodology by comparing calculated gamma-ray spectra with measurements performed at JET. The validation focuses on gamma-ray spectra measured by the tangential gamma-ray spectrometer during two JET three ion RF scenario discharges, performed in the JET 2019 deuterium experimental campaign. For validation the calculated plasma gamma-ray spectrum was combined with the neutron induced prompt gamma-ray background, originating in the vacuum vessel, and scaled to absolute values calculating the total number of plasma gamma-ray and neutron emitting reactions. The comparison between calculated and measured gamma-ray spectra shows good agreement with the shape of the calculated gamma-ray spectra matching that of measurements for both studied discharges. Moreover, the calculated absolute values of the gamma-ray spectra were of the same order of magnitude at the position of the gamma-ray detector located at the end of a long line-of-sight in a biological shield. The comparison has validated the developed plasma gamma-ray source methodology for MCNP photon transport calculations at JET. The validation provides a basis for the developed plasma gamma-ray source to be used as a support for the development of future tokamaks such as DEMO. [ABSTRACT FROM AUTHOR]

Published
2022
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24. Nonlinear contribution of neutral beam injection in TCV EC-heated advanced tokamak scenarios

Author

Vallar, M., Agostini, M., Bolzonella, T., Coda, S., Garcia, J., Geiger, B., Goodman, T., Gorelenkova, M., Karpushov, A.N., Kurki-Suonio, T., Piron, C., Pigatto, L., Sauter, O., Vianello, N., and Vincenzi, P.

Abstract

TCV is a tokamak device capable of many different plasma shapes, equipped with a flexible Electron Cyclotron (EC) system and since 2016 with a heating Neutral Beam (NB) injector. The EC system incorporates two subsystems: X2 (second harmonic) used for electron heating up to cutoff density with efficient current drive; X3 extends the density range for EC heating up to higher density (cutoff limit) suitable for H-mode confinement regime. The X2+X3 EC power available for the experiments studied here was 2.5 MW. The maximal NB power was up to 1.05 MW, using the tangentially injected beam with full energy of 25 keV at maximal power. Compared to the past, when fully non-inductive plasmas sustained using EC waves only were obtained, the operating space of advanced tokamak scenarios in TCV has been now extended towards higher plasma current and density with NB+EC heating scheme. These scenarios, characterized by high βN, high non-inductive current fraction and a relevant energetic particle (EP) population fraction (~10% ne) are envisaged as potential candidates for the regular future tokamak reactor operation due to their high fusion power generation and low inductive current requirements and outline the basis for future JT60-SA high-β experimental program. An internal transport barrier can be generated by reversing the q-profile using EC current-drive (ECCD). A strong contribution of bulk ions and EP to plasma pressure and total energy in performed plasma discharges is illustrated in Figure 1: the plasma β is clearly decorrelated from electron thermal energy and this is caused by an interplay between neutral beam injection (NBI) and ECH., The 45th European Physical Society Conference on Plasma Physics

Published
2018

25. Nonlinear contribution of neutral beam injection in TCV EC - heated advanced tokamak scenarios

Author

Vallar M., Agostini M., Bolzonella T., Coda S., Garcia J., Geiger B., Giruzzi G., Goodman T., Gorelenkova M., Karpushov A.N., Kurki-Suonio T., Piron C., Pigatto L., Sauter O., Vianello N., Vincenzi P., Yoshida M., TCV team, and MST1 team

Subjects
electron runaway, thermal quench, plasma physics
Abstract

TCV (Tokamak à Configuration Variable) is a tokamak device capable of many different plasma shape s and positions, equipped with a flexible system of Electron Cyclotron (EC) antennas and a new Neutral Beam (NB) injector [1] . The auxiliary power from the beam can reach 1 MW and it is injected tangentially co - current , coupling mostly with ions . This heating system allows n e w insights on advanced tokamak scenarios in TCV which, up to now , have been performed only with EC heating (ECH) . These scenarios have high ? N , high non - inductive current fraction and a relevant energetic particle (EP) population fraction (?10 %) . An internal transport barrier can be generated by reversing the q - profile using EC current - drive (ECCD) [2] . In this work we show that the effect of the sum of the two heating sources (NBI and EC H ) in TCV high ? N plasmas is not linear, and interpretative modelling is carried out to understand the behaviour of the NB EP s when ECH is present . A statistical study on a set of experiments with both ECH and NBI is presented to show t he effect of NB injection (NBI) on plasma performance: ? N and the plasma stored energy do n o t increase linearly with NB power. Furthermore, the contribution to the total plasma current from ohmic transformer, bootstra p current and current drive are respectively estimated , showing that EC has a strong impact on Z eff , modifying therefore the plasma resistivity and the ohmic contribution to the current. This effect is taken into account when applying the Monte Carlo inter pretative NBI code NUBEAM. It results that with the combined application of ECRH and ECCD , the electron temperature and plasma equilibrium change significantly, impacting on the NB power deposition: CX and orbit losses tend to increase, reducing by 20% the power deposited on plasma species. Modelling suggests that the variation in T e changes the EP power redistribution among the species, transfe rring more power to the ions. The impact on EP s orbit given by ECCD equilibrium modification is performed with the Monte Carlo ASCOT code for NBI modelling , capable of solving the EP full gyro - motion.

Published
2018

26. Reduced energetic particle transport models enable comprehensive time-dependent tokamak simulations

Author

Podestà, M., primary, Bardóczi, L., additional, Collins, C.S., additional, Gorelenkov, N.N., additional, Heidbrink, W.W., additional, Duarte, V.N., additional, Kramer, G.J., additional, Fredrickson, E.D., additional, Gorelenkova, M., additional, Kim, D., additional, Liu, D., additional, Poli, F.M., additional, Van Zeeland, M.A., additional, and White, R.B., additional

Published
2019
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28. Validation of neutron emission and neutron energy spectrum calculations on a Mega Ampere Spherical Tokamak with directional relativistic spectrum simulator.

Author

Sperduti, A, Klimek, I, Conroy, S, Cecconello, M, Gorelenkova, M, and Snicker, A

Subjects
NEUTRON temperature, NEUTRON flux, NEUTRON emission, FAST ions, NUMERICAL calculations, NEUTRONS
Abstract

The recently developed directional relativistic spectrum simulator (DRESS) code has been validated for the first time against numerical calculations and experimental measurements performed on the Mega Ampere Spherical Tokamak. In this validation, the neutron emissivities and rates computed by DRESS are benchmarked against TRANSP/NUBEAM predictions while the neutron energy spectra provided by DRESS taking as input TRANSP/NUBEAM and ASCOT/BBNBI in Gyro-Orbit mode fast ion distributions are validated against proton pulse height spectra measured by the neutron flux monitor. Excellent agreement was found between DRESS and TRANSP/NUBEAM predictions of local and total neutron emission. [ABSTRACT FROM AUTHOR]

Published
2021
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30. Overview of recent physics results from MAST

Author

Andrew, Kirk, Adamek, J, Akers, Rj, Allan, S, Appel, L, F Arese Lucini, Barnes, M, Barrett, T, N Ben Ayed, Boeglin, W, Bradley, J, Browning, Pk, Brunner, J, Cahyna, P, Cardnell, S, Meghan, Carr, Casson, Federica, Marco, Cecconello, Challis, C, Chapman, It, Chapman, S, Chorley, J, Sean, Conroy, Conway, N, Cooper, Wa, Cox, M, Crocker, N, Crowley, B, Cunningham, G, Danilov, A, Darrow, D, Dendy, R, Dickinson, D, Dorland, W, Dudson, B, Dunai, D, Easy, L, Elmore, S, Evans, KAREN MARILYN, Farley, T, Fedorczak, N, Field, A, Fishpool, G, Fitzgerald, I, Fox, M, Freethy, S, Garzotti, L, Ghim, Yc, K, Gi, Gibson, K, Gorelenkova, M, Gracias, W, Gurl, C, Guttenfelder, W, Ham, C, Harrison, J, Harting, D, Havlickova, E, Hawkes, N, Hender, T, Henderson, S, Highcock, E, Hillesheim, J, Hnat, B, Horacek, J, Zehr, HOWARD JAY, Howell, D, Huang, B, Imada, K, Inomoto, M, Imazawa, R, Jones, O, Kadowaki, K, Kaye, S, Keeling, D, Iwona, Klimek, Kocan, M, Kogan, L, Komm, M, Lai, W, Leddy, J, Leggate, H, Hollocombe, J, Lipschultz, B, Lisgo, S, Liu, Yq, Lloyd, B, Lomanowski, B, Lukin, V, Lupelli, I, Maddison, G, Jens, Madsen, Mailloux, J, Martin, R, Mcardle, G, Mcclements, K, Mcmillan, B, Meakins, A, Meyer, H, Michael, C, Militello, F, Milnes, J, Morris, Aw, Motojima, G, Derek, Muir, Naylor, G, Nielsen, A, O’Brien, M, O’Gorman, T, O’Mullane, M, Olsen, J, Omotani, J, Ono, Y, Pamela, S, Pangione, L, Parra, F, Patel, A, Peebles, W, ALVAREZ PEREZ, PEDRO RICCARDO, Pinches, S, Piron, L, Price, ALEXANDER MARCUS, Reinke, M, Ricci, P, Riva, F, Roach, C, Romanelli, M, Ryan, D, Saarelma, S, Saveliev, A, Scannell, R, Schekochihin, A, Sharapov, S, Sharples, R, Shevchenko, V, Shinohara, K, Silburn, S, Simpson, J, Stanier, A, Storrs, J, Summers, H, Takase, Y, Tamain, P, Tanabe, H, Tanaka, H, Tani, K, WILLIAMSON TAYLOR, DEBIE CLAUDIA, Thomas, DEEPA ROSE, Thomas-Davies, N, and Thornton, A

Published
2017

33. Overview of recent physics results from MAST

Author

Kirk, A., Adamek, J., Akers, R. J., Allan, S., Appel, L., Lucini, F. Arese, Barnes, M., Barrett, T., Ben Ayed, N., Boeglin, W., Bradley, J., Browning, P. K., Brunner, J., Cahyna, P., Cardnell, S., Carr, M., Casson, F., Cecconello, Marco, Challis, C., Chapman, I. T., Chapman, S., Chorley, J., Conroy, Sean, Conway, N., Cooper, W. A., Cox, M., Crocker, N., Crowley, B., Cunningham, G., Danilov, A., Darrow, D., Dendy, R., Dickinson, D., Dorland, W., Dudson, B., Dunai, D., Easy, L., Elmore, S., Evans, M., Farley, T., Fedorczak, N., Field, A., Fishpool, G., Fitzgerald, I., Fox, M., Freethy, S., Garzotti, L., Ghim, Y. C., Gi, K., Gibson, K., Gorelenkova, M., Gracias, W., Gurl, C., Guttenfelder, W., Ham, C., Harrison, J., Harting, D., Havlickova, E., Hawkes, N., Hender, T., Henderson, S., Highcock, E., Hillesheim, J., Hnat, B., Horacek, J., Howard, J., Howell, D., Huang, B., Imada, K., Inomoto, M., Imazawa, R., Jones, O., Kadowaki, K., Kaye, S., Keeling, D., Klimek, Iwona, Kocan, M., Kogan, L., Komm, M., Lai, W., Leddy, J., Leggate, H., Hollocombe, J., Lipschultz, B., Lisgo, S., Liu, Y. Q., Lloyd, B., Lomanowski, B., Lukin, V., Lupelli, I., Maddison, G., Madsen, J., Mailloux, J., Martin, R., McArdle, G., McClements, K., McMillan, B., Meakins, A., Meyer, H., Michael, C., Militello, F., Milnes, J., Morris, A. W., Motojima, G., Muir, D., Naylor, G., Nielsen, A., O'Brien, M., O'Gorman, T., O'Mullane, M., Olsen, J., Omotani, J., Ono, Y., Pamela, S., Pangione, L., Parra, F., Patel, A., Peebles, W., Perez, R., Pinches, S., Piron, L., Price, M., Reinke, M., Ricci, P., Riva, F., Roach, C., Romanelli, M., Ryan, D., Saarelma, S., Saveliev, A., Scannell, R., Schekochihin, A., Sharapov, S., Sharples, R., Shevchenko, V., Shinohara, K., Silburn, S., Simpson, J., Stanier, A., Storrs, J., Summers, H., Takase, Y., Tamain, P., Tanabe, H., Tanaka, H., Tani, K., Taylor, D., Thomas, D., Thomas-Davies, N., Thornton, A., Turnyanskiy, M., Valovic, M., Vann, R., Van Wyk, F., Walkden, N., Watanabe, T., Wilson, H., Wischmeier, M., Yamada, T., Young, J., Zoletnik, S., Kirk, A., Adamek, J., Akers, R. J., Allan, S., Appel, L., Lucini, F. Arese, Barnes, M., Barrett, T., Ben Ayed, N., Boeglin, W., Bradley, J., Browning, P. K., Brunner, J., Cahyna, P., Cardnell, S., Carr, M., Casson, F., Cecconello, Marco, Challis, C., Chapman, I. T., Chapman, S., Chorley, J., Conroy, Sean, Conway, N., Cooper, W. A., Cox, M., Crocker, N., Crowley, B., Cunningham, G., Danilov, A., Darrow, D., Dendy, R., Dickinson, D., Dorland, W., Dudson, B., Dunai, D., Easy, L., Elmore, S., Evans, M., Farley, T., Fedorczak, N., Field, A., Fishpool, G., Fitzgerald, I., Fox, M., Freethy, S., Garzotti, L., Ghim, Y. C., Gi, K., Gibson, K., Gorelenkova, M., Gracias, W., Gurl, C., Guttenfelder, W., Ham, C., Harrison, J., Harting, D., Havlickova, E., Hawkes, N., Hender, T., Henderson, S., Highcock, E., Hillesheim, J., Hnat, B., Horacek, J., Howard, J., Howell, D., Huang, B., Imada, K., Inomoto, M., Imazawa, R., Jones, O., Kadowaki, K., Kaye, S., Keeling, D., Klimek, Iwona, Kocan, M., Kogan, L., Komm, M., Lai, W., Leddy, J., Leggate, H., Hollocombe, J., Lipschultz, B., Lisgo, S., Liu, Y. Q., Lloyd, B., Lomanowski, B., Lukin, V., Lupelli, I., Maddison, G., Madsen, J., Mailloux, J., Martin, R., McArdle, G., McClements, K., McMillan, B., Meakins, A., Meyer, H., Michael, C., Militello, F., Milnes, J., Morris, A. W., Motojima, G., Muir, D., Naylor, G., Nielsen, A., O'Brien, M., O'Gorman, T., O'Mullane, M., Olsen, J., Omotani, J., Ono, Y., Pamela, S., Pangione, L., Parra, F., Patel, A., Peebles, W., Perez, R., Pinches, S., Piron, L., Price, M., Reinke, M., Ricci, P., Riva, F., Roach, C., Romanelli, M., Ryan, D., Saarelma, S., Saveliev, A., Scannell, R., Schekochihin, A., Sharapov, S., Sharples, R., Shevchenko, V., Shinohara, K., Silburn, S., Simpson, J., Stanier, A., Storrs, J., Summers, H., Takase, Y., Tamain, P., Tanabe, H., Tanaka, H., Tani, K., Taylor, D., Thomas, D., Thomas-Davies, N., Thornton, A., Turnyanskiy, M., Valovic, M., Vann, R., Van Wyk, F., Walkden, N., Watanabe, T., Wilson, H., Wischmeier, M., Yamada, T., Young, J., and Zoletnik, S.

Abstract

New results from MAST are presented that focus on validating models in order to extrapolate to future devices. Measurements during start-up experiments have shown how the bulk ion temperature rise scales with the square of the reconnecting field. During the current ramp-up, models are not able to correctly predict the current diffusion. Experiments have been performed looking at edge and core turbulence. At the edge, detailed studies have revealed how filament characteristics are responsible for determining the near and far scrape off layer density profiles. In the core the intrinsic rotation and electron scale turbulence have been measured. The role that the fast ion gradient has on redistributing fast ions through fishbone modes has led to a redesign of the neutral beam injector on MAST Upgrade. In H-mode the turbulence at the pedestal top has been shown to be consistent with being due to electron temperature gradient modes. A reconnection process appears to occur during edge localized modes (ELMs) and the number of filaments released determines the power profile at the divertor. Resonant magnetic perturbations can mitigate ELMs provided the edge peeling response is maximised and the core kink response minimised. The mitigation of intrinsic error fields with toroidal mode number n > 1 has been shown to be important for plasma performance.

Published
2017
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34. Progress in the ITER Integrated Modelling Programme and the use and validation of IMAS within the ITER Members

Author

Pinches, S, Akers, R, Andre, R, Aniel, T, Bandyopadhyay, I, Basiuk, V, Belli, E, Bonnin, X, Candy, J, Chattopadhyay, A, Dekeyser, W, Van Dellen, L, Faugeras, B, Fukuyama, A, Gorelenkova, M, Hosokawa, M, Huijsmans, G, Huynh, P, Ide, S, Imbeaux, Frédéric, Jhang, H, Johnson, I, Johnson, T, Jung, L, Khayrutdinov, R, Kim, S, Konovalov, S, Kos, L, Lao, L, Liu, Y, Lodestro, L, Lukash, V, Lupelli, I, Medvedev, S, Meneghini, O, Meyer, W, Muir, D, Naito, O, Nardon, E, Poli, F, Polevoi, A, Sauter, O, Schneider, M, Singh, A, Snyder, P, Staebler, G, Strand, P, Suzuki, M, Wiesen, S, Zhao, D, ITER organization (ITER), Culham Centre for Fusion Energy (CCFE), Princeton Plasma Physics Laboratory (PPPL), Princeton University, Institut de Recherche sur la Fusion par confinement Magnétique (IRFM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institute for Plasma Research [Gandhinagar], General Atomics [San Diego], 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 (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), Kyoto University, Department of Nuclear Engineering, Kyoto University, 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), and Kyoto University [Kyoto]

Subjects
[INFO.INFO-MO]Computer Science [cs]/Modeling and Simulation, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2016

36. Overview of recent physics results from MAST

Author

Kirk, A., primary, Adamek, J., additional, Akers, R.J., additional, Allan, S., additional, Appel, L., additional, Arese Lucini, F., additional, Barnes, M., additional, Barrett, T., additional, Ben Ayed, N., additional, Boeglin, W., additional, Bradley, J., additional, Browning, P.K., additional, Brunner, J., additional, Cahyna, P., additional, Cardnell, S., additional, Carr, M., additional, Casson, F., additional, Cecconello, M., additional, Challis, C., additional, Chapman, I.T., additional, Chapman, S., additional, Chorley, J., additional, Conroy, S., additional, Conway, N., additional, Cooper, W.A., additional, Cox, M., additional, Crocker, N., additional, Crowley, B., additional, Cunningham, G., additional, Danilov, A., additional, Darrow, D., additional, Dendy, R., additional, Dickinson, D., additional, Dorland, W., additional, Dudson, B., additional, Dunai, D., additional, Easy, L., additional, Elmore, S., additional, Evans, M., additional, Farley, T., additional, Fedorczak, N., additional, Field, A., additional, Fishpool, G., additional, Fitzgerald, I., additional, Fox, M., additional, Freethy, S., additional, Garzotti, L., additional, Ghim, Y.C., additional, Gi, K., additional, Gibson, K., additional, Gorelenkova, M., additional, Gracias, W., additional, Gurl, C., additional, Guttenfelder, W., additional, Ham, C., additional, Harrison, J., additional, Harting, D., additional, Havlickova, E., additional, Hawkes, N., additional, Hender, T., additional, Henderson, S., additional, Highcock, E., additional, Hillesheim, J., additional, Hnat, B., additional, Horacek, J., additional, Howard, J., additional, Howell, D., additional, Huang, B., additional, Imada, K., additional, Inomoto, M., additional, Imazawa, R., additional, Jones, O., additional, Kadowaki, K., additional, Kaye, S., additional, Keeling, D., additional, Klimek, I., additional, Kocan, M., additional, Kogan, L., additional, Komm, M., additional, Lai, W., additional, Leddy, J., additional, Leggate, H., additional, Hollocombe, J., additional, Lipschultz, B., additional, Lisgo, S., additional, Liu, Y.Q., additional, Lloyd, B., additional, Lomanowski, B., additional, Lukin, V., additional, Lupelli, I., additional, Maddison, G., additional, Madsen, J., additional, Mailloux, J., additional, Martin, R., additional, McArdle, G., additional, McClements, K., additional, McMillan, B., additional, Meakins, A., additional, Meyer, H., additional, Michael, C., additional, Militello, F., additional, Milnes, J., additional, Morris, A.W., additional, Motojima, G., additional, Muir, D., additional, Naylor, G., additional, Nielsen, A., additional, O’Brien, M., additional, O’Gorman, T., additional, O’Mullane, M., additional, Olsen, J., additional, Omotani, J., additional, Ono, Y., additional, Pamela, S., additional, Pangione, L., additional, Parra, F., additional, Patel, A., additional, Peebles, W., additional, Perez, R., additional, Pinches, S., additional, Piron, L., additional, Price, M., additional, Reinke, M., additional, Ricci, P., additional, Riva, F., additional, Roach, C., additional, Romanelli, M., additional, Ryan, D., additional, Saarelma, S., additional, Saveliev, A., additional, Scannell, R., additional, Schekochihin, A., additional, Sharapov, S., additional, Sharples, R., additional, Shevchenko, V., additional, Shinohara, K., additional, Silburn, S., additional, Simpson, J., additional, Stanier, A., additional, Storrs, J., additional, Summers, H., additional, Takase, Y., additional, Tamain, P., additional, Tanabe, H., additional, Tanaka, H., additional, Tani, K., additional, Taylor, D., additional, Thomas, D., additional, Thomas-Davies, N., additional, Thornton, A., additional, Turnyanskiy, M., additional, Valovic, M., additional, Vann, R., additional, Van Wyk, F., additional, Walkden, N., additional, Watanabe, T., additional, Wilson, H., additional, Wischmeier, M., additional, Yamada, T., additional, Young, J., additional, and Zoletnik, S., additional

Published
2017
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42. TRANSP modelling of total and local neutron emission on MAST

Author

Klimek, Iwona, Cecconello, Marco, Gorelenkova, M., Keeling, D., Meakins, A., Jones, O., Akers, R., Lupelli, I., Turnyanskiy, M., Ericsson, Göran, Klimek, Iwona, Cecconello, Marco, Gorelenkova, M., Keeling, D., Meakins, A., Jones, O., Akers, R., Lupelli, I., Turnyanskiy, M., and Ericsson, Göran

Abstract

The results of TRANSP simulations of neutron count rate profiles measured by a collimated neutron flux monitor-neutron camera (NC)-for different plasma scenarios on MAST are reported. In addition, the effect of various plasma parameters on neutron emission is studied by means of TRANSP simulation. The fast ion redistribution and losses due to fishbone modes, which belong to a wider category of energetic particle modes, are observed by the NC and modelled in TRANSP.

Published
2015
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43. Energetic ion transport by microturbulence is insignificant in tokamaks

Author

Massachusetts Institute of Technology. Department of Nuclear Science and Engineering, White, Anne E., Pace, David C., Austin, M. E., Bass, E. M., Budny, R. V., Heidbrink, W. W., Hillesheim, J. C., Holcomb, C. T., Gorelenkova, M., Grierson, B. A., McCune, D. C., McKee, G. R., Muscatello, C. M., Park, J. M., Petty, C. C., Rhodes, T. L., Staebler, G. M., Suzuki, T., Van Zeeland, M. A., Waltz, R. E., Wang, G., Yan, Z., Yuan, X., Zhu, Y. B., Massachusetts Institute of Technology. Department of Nuclear Science and Engineering, White, Anne E., Pace, David C., Austin, M. E., Bass, E. M., Budny, R. V., Heidbrink, W. W., Hillesheim, J. C., Holcomb, C. T., Gorelenkova, M., Grierson, B. A., McCune, D. C., McKee, G. R., Muscatello, C. M., Park, J. M., Petty, C. C., Rhodes, T. L., Staebler, G. M., Suzuki, T., Van Zeeland, M. A., Waltz, R. E., Wang, G., Yan, Z., Yuan, X., and Zhu, Y. B.

Abstract

Energetic ion transport due to microturbulence is investigated in magnetohydrodynamic-quiescent plasmas by way of neutral beam injection in the DIII-D tokamak [J. L. Luxon, Nucl. Fusion 42, 614 (2002)]. A range of on-axis and off-axis beam injection scenarios are employed to vary relevant parameters such as the character of the background microturbulence and the value of Eb/Te , where Eb is the energetic ion energy and Te the electron temperature. In all cases, it is found that any transport enhancement due to microturbulence is too small to observe experimentally. These transport effects are modeled using numerical and analytic expectations that calculate the energetic ion diffusivity due to microturbulence. It is determined that energetic ion transport due to coherent fluctuations (e.g., Alfvén eigenmodes) is a considerably larger effect and should therefore be considered more important for ITER., United States. Dept. of Energy (DE-FC02-04ER54698), United States. Dept. of Energy (DE-FC02-99ER54512), United States. Dept. of Energy (DE-FG03-97ER54415), United States. Dept. of Energy (DE-FG02-07ER54917), United States. Dept. of Energy (DE-AC02-09CH11466), United States. Dept. of Energy (SC-G903402), United States. Dept. of Energy (DE-FG02-08ER54984), United States. Dept. of Energy ( DE-AC52-07NA27344), United States. Dept. of Energy ( DE-FG02-89ER53296), United States. Dept. of Energy (DE-FG02-08ER54999), United States. Dept. of Energy (DE-AC05-00OR22725)

Published
2015

49. Measurements and modeling of Alfvén eigenmode induced fast ion transport and loss in DIII-D and ASDEX Upgrade

Author

Zeeland, van, M.A., Heidbrink, W.W., Fisher, R.K., García-Munoz, M., Kramer, G.J., Pace, D.C., White, R.B., Aekaeslompolo, R.B., Austin, M.D., Boom, J.E., Classen, I.G.J., Graça, da, S., Geiger, B., Gorelenkova, M., Gorenlenkov, N.N., Hyatt, A.W., Luhmann, N.C., Maraschek, M., McKee, G.R., Moyer, R.A., Muscatello, C.M., Nazikian, R., Park, H.K., Sharapov, S., Suttrop, W., Tardini, G., Tobias, B.J., Zhu, Y.B., Zeeland, van, M.A., Heidbrink, W.W., Fisher, R.K., García-Munoz, M., Kramer, G.J., Pace, D.C., White, R.B., Aekaeslompolo, R.B., Austin, M.D., Boom, J.E., Classen, I.G.J., Graça, da, S., Geiger, B., Gorelenkova, M., Gorenlenkov, N.N., Hyatt, A.W., Luhmann, N.C., Maraschek, M., McKee, G.R., Moyer, R.A., Muscatello, C.M., Nazikian, R., Park, H.K., Sharapov, S., Suttrop, W., Tardini, G., Tobias, B.J., and Zhu, Y.B.

Abstract

Neutral beam injection into reversed magnetic shear DIII-D and ASDEX Upgrade plasmas produces a variety of Alfvénic activity including toroidicity-induced Alfvén eigenmodes and reversed shear Alfvén eigenmodes (RSAEs). These modes are studied during the discharge current ramp phase when incomplete current penetration results in a high central safety factor and increased drive due to multiple higher order resonances. Scans of injected 80 keV neutral beam power on DIII-D showed a transition from classical to AE dominated fast ion transport and, as previously found, discharges with strong AE activity exhibit a deficit in neutron emission relative to classical predictions. By keeping beam power constant and delaying injection during the current ramp, AE activity was reduced or eliminated and a significant improvement in fast ion confinement observed. Similarly, experiments in ASDEX Upgrade using early 60 keV neutral beam injection drove multiple unstable RSAEs. Periods of strong RSAE activity are accompanied by a large (peak dSn=Sn ?? 60%) neutron deficit. Losses of beam ions modulated at AE frequencies were observed using large bandwidth energy and pitch resolving fast ion loss scintillator detectors and clearly identify their role in the process. Modeling of DIII-D loss measurements using guiding center following codes to track particles in the presence of ideal magnetohydrodynamic (MHD) calculated AE structures (validated by comparison to experiment) is able to reproduce the dominant energy, pitch, and temporal evolution of these losses. While loss of both co and counter current fast ions occurs, simulations show that the dominant loss mechanism observed is the mode induced transition of counter-passing fast ions to lost trapped orbits. Modeling also reproduces a coherent signature of AE induced losses and it was found that these coherent losses scale proportionally with the amplitude; an additional incoherent contribution scales quadratically with the mode amplitude

Published
2011

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