NBI Modulation Experiments to Study Momentum Transport and Magnetic Field Induced Ripple Torque on JET

Tuomas Tala, Antti Salmi, P. Mantica, C. Angioni, G Corrigan, P.C. de Vries, C. Giroud, J. Ferreira, J. Lönnroth, V. Naulin, A.G. Peeters, W. Solomon, D. Strintzi, M. Tsalas, T.W. Versloot, J. Weiland, K.-D. Zastrow, JET-EFDA collaborators

    Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientificpeer-review

    Abstract

    Several parametric scans have been performed to study momentum transport on JET. NBI modulation technique has been applied to separating the diffusive and convective momentum transport terms. The magnitude of the inward momentum pinch depends strongly on the inverse density gradient length, with an experimental scaling for the pinch number being $-Rv_{pinch}/\chi\phi = 1.2R/L_n + 1.4$. There is no dependence of the pinch number on collisionality. The Prandtl number was not found to depend either on R/Ln, collisionality or on q. The gyrokinetic simulations show qualitatively similar dependence of the pinch number on R/Ln, but the dependence is weaker in the simulations. Gyro-kinetic simulations do not find any clear parametric dependence in the Prandtl number, in agreement with experiments, but the experimental values are larger than the simulated ones. The extrapolation of these results to ITER illustrates that at R/Ln>2 the pinch number becomes large enough (> 3-4) to make the rotation profile peaked provided that the edge rotation is non-zero. And this rotation peaking can be achieved with small or even with no core torque source. The absolute value of the core rotation is still very challenging to predict partly due to the lack of the present knowledge of the rotation at the plasma edge, partly due to insufficient understanding of 3D effects like braking and partly due to the uncertainties in the extrapolation of the present momentum transport results to a larger device.
    Original languageEnglish
    Title of host publicationProceedings
    Subtitle of host publication38th EPS Conference on Plasma Physics, EPS 2011
    EditorsA. Becoulet
    PublisherEuropean Physical Society
    Pages605-608
    Volume1
    ISBN (Print)2-914771-68-1, 978-1-6183-9593-1
    Publication statusPublished - 2011
    MoE publication typeA4 Article in a conference publication
    Event38th EPS Conference on Plasma Physics - Strasbourg, France
    Duration: 27 Jun 20111 Jul 2011

    Conference

    Conference38th EPS Conference on Plasma Physics
    Abbreviated titleEPS 2011
    CountryFrance
    CityStrasbourg
    Period27/06/111/07/11

    Fingerprint

    ripples
    torque
    momentum
    modulation
    magnetic fields
    Prandtl number
    extrapolation
    braking
    simulation
    scaling
    gradients
    kinetics
    profiles

    Keywords

    • plasma physics

    Cite this

    Tala, T., Salmi, A., Mantica, P., Angioni, C., Corrigan, G., Vries, P. C. D., ... JET-EFDA collaborators (2011). NBI Modulation Experiments to Study Momentum Transport and Magnetic Field Induced Ripple Torque on JET. In A. Becoulet (Ed.), Proceedings: 38th EPS Conference on Plasma Physics, EPS 2011 (Vol. 1, pp. 605-608). European Physical Society.
    Tala, Tuomas ; Salmi, Antti ; Mantica, P. ; Angioni, C. ; Corrigan, G ; Vries, P.C. de ; Giroud, C. ; Ferreira, J. ; Lönnroth, J. ; Naulin, V. ; Peeters, A.G. ; Solomon, W. ; Strintzi, D. ; Tsalas, M. ; Versloot, T.W. ; Weiland, J. ; Zastrow, K.-D. ; JET-EFDA collaborators. / NBI Modulation Experiments to Study Momentum Transport and Magnetic Field Induced Ripple Torque on JET. Proceedings: 38th EPS Conference on Plasma Physics, EPS 2011. editor / A. Becoulet. Vol. 1 European Physical Society, 2011. pp. 605-608
    @inproceedings{7d0390d34e324e0a807da4d287ead307,
    title = "NBI Modulation Experiments to Study Momentum Transport and Magnetic Field Induced Ripple Torque on JET",
    abstract = "Several parametric scans have been performed to study momentum transport on JET. NBI modulation technique has been applied to separating the diffusive and convective momentum transport terms. The magnitude of the inward momentum pinch depends strongly on the inverse density gradient length, with an experimental scaling for the pinch number being $-Rv_{pinch}/\chi\phi = 1.2R/L_n + 1.4$. There is no dependence of the pinch number on collisionality. The Prandtl number was not found to depend either on R/Ln, collisionality or on q. The gyrokinetic simulations show qualitatively similar dependence of the pinch number on R/Ln, but the dependence is weaker in the simulations. Gyro-kinetic simulations do not find any clear parametric dependence in the Prandtl number, in agreement with experiments, but the experimental values are larger than the simulated ones. The extrapolation of these results to ITER illustrates that at R/Ln>2 the pinch number becomes large enough (> 3-4) to make the rotation profile peaked provided that the edge rotation is non-zero. And this rotation peaking can be achieved with small or even with no core torque source. The absolute value of the core rotation is still very challenging to predict partly due to the lack of the present knowledge of the rotation at the plasma edge, partly due to insufficient understanding of 3D effects like braking and partly due to the uncertainties in the extrapolation of the present momentum transport results to a larger device.",
    keywords = "plasma physics",
    author = "Tuomas Tala and Antti Salmi and P. Mantica and C. Angioni and G Corrigan and Vries, {P.C. de} and C. Giroud and J. Ferreira and J. L{\"o}nnroth and V. Naulin and A.G. Peeters and W. Solomon and D. Strintzi and M. Tsalas and T.W. Versloot and J. Weiland and K.-D. Zastrow and {JET-EFDA collaborators}",
    year = "2011",
    language = "English",
    isbn = "2-914771-68-1",
    volume = "1",
    pages = "605--608",
    editor = "A. Becoulet",
    booktitle = "Proceedings",
    publisher = "European Physical Society",
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    Tala, T, Salmi, A, Mantica, P, Angioni, C, Corrigan, G, Vries, PCD, Giroud, C, Ferreira, J, Lönnroth, J, Naulin, V, Peeters, AG, Solomon, W, Strintzi, D, Tsalas, M, Versloot, TW, Weiland, J, Zastrow, K-D & JET-EFDA collaborators 2011, NBI Modulation Experiments to Study Momentum Transport and Magnetic Field Induced Ripple Torque on JET. in A Becoulet (ed.), Proceedings: 38th EPS Conference on Plasma Physics, EPS 2011. vol. 1, European Physical Society, pp. 605-608, 38th EPS Conference on Plasma Physics, Strasbourg, France, 27/06/11.

    NBI Modulation Experiments to Study Momentum Transport and Magnetic Field Induced Ripple Torque on JET. / Tala, Tuomas; Salmi, Antti; Mantica, P.; Angioni, C.; Corrigan, G; Vries, P.C. de; Giroud, C.; Ferreira, J.; Lönnroth, J.; Naulin, V.; Peeters, A.G.; Solomon, W.; Strintzi, D.; Tsalas, M.; Versloot, T.W.; Weiland, J.; Zastrow, K.-D.; JET-EFDA collaborators.

    Proceedings: 38th EPS Conference on Plasma Physics, EPS 2011. ed. / A. Becoulet. Vol. 1 European Physical Society, 2011. p. 605-608.

    Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientificpeer-review

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    T1 - NBI Modulation Experiments to Study Momentum Transport and Magnetic Field Induced Ripple Torque on JET

    AU - Tala, Tuomas

    AU - Salmi, Antti

    AU - Mantica, P.

    AU - Angioni, C.

    AU - Corrigan, G

    AU - Vries, P.C. de

    AU - Giroud, C.

    AU - Ferreira, J.

    AU - Lönnroth, J.

    AU - Naulin, V.

    AU - Peeters, A.G.

    AU - Solomon, W.

    AU - Strintzi, D.

    AU - Tsalas, M.

    AU - Versloot, T.W.

    AU - Weiland, J.

    AU - Zastrow, K.-D.

    AU - JET-EFDA collaborators

    PY - 2011

    Y1 - 2011

    N2 - Several parametric scans have been performed to study momentum transport on JET. NBI modulation technique has been applied to separating the diffusive and convective momentum transport terms. The magnitude of the inward momentum pinch depends strongly on the inverse density gradient length, with an experimental scaling for the pinch number being $-Rv_{pinch}/\chi\phi = 1.2R/L_n + 1.4$. There is no dependence of the pinch number on collisionality. The Prandtl number was not found to depend either on R/Ln, collisionality or on q. The gyrokinetic simulations show qualitatively similar dependence of the pinch number on R/Ln, but the dependence is weaker in the simulations. Gyro-kinetic simulations do not find any clear parametric dependence in the Prandtl number, in agreement with experiments, but the experimental values are larger than the simulated ones. The extrapolation of these results to ITER illustrates that at R/Ln>2 the pinch number becomes large enough (> 3-4) to make the rotation profile peaked provided that the edge rotation is non-zero. And this rotation peaking can be achieved with small or even with no core torque source. The absolute value of the core rotation is still very challenging to predict partly due to the lack of the present knowledge of the rotation at the plasma edge, partly due to insufficient understanding of 3D effects like braking and partly due to the uncertainties in the extrapolation of the present momentum transport results to a larger device.

    AB - Several parametric scans have been performed to study momentum transport on JET. NBI modulation technique has been applied to separating the diffusive and convective momentum transport terms. The magnitude of the inward momentum pinch depends strongly on the inverse density gradient length, with an experimental scaling for the pinch number being $-Rv_{pinch}/\chi\phi = 1.2R/L_n + 1.4$. There is no dependence of the pinch number on collisionality. The Prandtl number was not found to depend either on R/Ln, collisionality or on q. The gyrokinetic simulations show qualitatively similar dependence of the pinch number on R/Ln, but the dependence is weaker in the simulations. Gyro-kinetic simulations do not find any clear parametric dependence in the Prandtl number, in agreement with experiments, but the experimental values are larger than the simulated ones. The extrapolation of these results to ITER illustrates that at R/Ln>2 the pinch number becomes large enough (> 3-4) to make the rotation profile peaked provided that the edge rotation is non-zero. And this rotation peaking can be achieved with small or even with no core torque source. The absolute value of the core rotation is still very challenging to predict partly due to the lack of the present knowledge of the rotation at the plasma edge, partly due to insufficient understanding of 3D effects like braking and partly due to the uncertainties in the extrapolation of the present momentum transport results to a larger device.

    KW - plasma physics

    M3 - Conference article in proceedings

    SN - 2-914771-68-1

    SN - 978-1-6183-9593-1

    VL - 1

    SP - 605

    EP - 608

    BT - Proceedings

    A2 - Becoulet, A.

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    Tala T, Salmi A, Mantica P, Angioni C, Corrigan G, Vries PCD et al. NBI Modulation Experiments to Study Momentum Transport and Magnetic Field Induced Ripple Torque on JET. In Becoulet A, editor, Proceedings: 38th EPS Conference on Plasma Physics, EPS 2011. Vol. 1. European Physical Society. 2011. p. 605-608