Density profile peaking on DIII-D and JET – fuelling versus transport

Antti Salmi, Tuomas Tala, S. Mordijck, Hans Nordman, Jerry W. Hughes

Research output: Contribution to conferenceConference AbstractScientific

Abstract

Dimensionless collisionality (ν*) scans with fixed density in H-mode plasmas on DIII-D and JET together with modelling have shown that the NBI fuelling plays a more important role in density peaking than found in earlier multi-machine datasets where the increased peaking at low collisionality has been primarily ascribed to turbulent effects. Perturbative gas puff modulations are performed to disentangle the fuelling and the transport effects. On DIII-D, we find that, at the lowest ν*, the pinch is directed outward and the diffusion coefficients are larger compared to higher ν* cases. With increasing ν*, the pinch becomes inward outside the mid-radius, while remaining outward inside the mid-radius. At the same time, a strong increase in ion-scale density fluctuations with reduced ν* is observed with BES and predicted with TGLF. On JET, perturbative transport analysis, predictive integrated modelling with JINTRAC+TGLF and non-linear and linear GENE runs all show that NBI fuelling provides an important contribution to density peaking. These results indicate that the density profiles on ITER, where NBI fuelling is very small, may be less peaked than previously thought.
Original languageEnglish
Publication statusPublished - 2018
MoE publication typeNot Eligible
Event60th Annual Meeting of the APS Division of Plasma Physics - Portland, Portland, United States
Duration: 5 Nov 20189 Nov 2018
Conference number: 60
https://www.aps.org/units/dpp/meetings/annual/

Conference

Conference60th Annual Meeting of the APS Division of Plasma Physics
CountryUnited States
CityPortland
Period5/11/189/11/18
Internet address

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Salmi, A., Tala, T., Mordijck, S., Nordman, H., & Hughes, J. W. (2018). Density profile peaking on DIII-D and JET – fuelling versus transport. Abstract from 60th Annual Meeting of the APS Division of Plasma Physics, Portland, United States.
Salmi, Antti ; Tala, Tuomas ; Mordijck, S. ; Nordman, Hans ; Hughes, Jerry W. / Density profile peaking on DIII-D and JET – fuelling versus transport. Abstract from 60th Annual Meeting of the APS Division of Plasma Physics, Portland, United States.
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title = "Density profile peaking on DIII-D and JET – fuelling versus transport",
abstract = "Dimensionless collisionality (ν*) scans with fixed density in H-mode plasmas on DIII-D and JET together with modelling have shown that the NBI fuelling plays a more important role in density peaking than found in earlier multi-machine datasets where the increased peaking at low collisionality has been primarily ascribed to turbulent effects. Perturbative gas puff modulations are performed to disentangle the fuelling and the transport effects. On DIII-D, we find that, at the lowest ν*, the pinch is directed outward and the diffusion coefficients are larger compared to higher ν* cases. With increasing ν*, the pinch becomes inward outside the mid-radius, while remaining outward inside the mid-radius. At the same time, a strong increase in ion-scale density fluctuations with reduced ν* is observed with BES and predicted with TGLF. On JET, perturbative transport analysis, predictive integrated modelling with JINTRAC+TGLF and non-linear and linear GENE runs all show that NBI fuelling provides an important contribution to density peaking. These results indicate that the density profiles on ITER, where NBI fuelling is very small, may be less peaked than previously thought.",
author = "Antti Salmi and Tuomas Tala and S. Mordijck and Hans Nordman and Hughes, {Jerry W.}",
year = "2018",
language = "English",
note = "60th Annual Meeting of the APS Division of Plasma Physics ; Conference date: 05-11-2018 Through 09-11-2018",
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Salmi, A, Tala, T, Mordijck, S, Nordman, H & Hughes, JW 2018, 'Density profile peaking on DIII-D and JET – fuelling versus transport' 60th Annual Meeting of the APS Division of Plasma Physics, Portland, United States, 5/11/18 - 9/11/18, .

Density profile peaking on DIII-D and JET – fuelling versus transport. / Salmi, Antti; Tala, Tuomas; Mordijck, S.; Nordman, Hans; Hughes, Jerry W.

2018. Abstract from 60th Annual Meeting of the APS Division of Plasma Physics, Portland, United States.

Research output: Contribution to conferenceConference AbstractScientific

TY - CONF

T1 - Density profile peaking on DIII-D and JET – fuelling versus transport

AU - Salmi, Antti

AU - Tala, Tuomas

AU - Mordijck, S.

AU - Nordman, Hans

AU - Hughes, Jerry W.

PY - 2018

Y1 - 2018

N2 - Dimensionless collisionality (ν*) scans with fixed density in H-mode plasmas on DIII-D and JET together with modelling have shown that the NBI fuelling plays a more important role in density peaking than found in earlier multi-machine datasets where the increased peaking at low collisionality has been primarily ascribed to turbulent effects. Perturbative gas puff modulations are performed to disentangle the fuelling and the transport effects. On DIII-D, we find that, at the lowest ν*, the pinch is directed outward and the diffusion coefficients are larger compared to higher ν* cases. With increasing ν*, the pinch becomes inward outside the mid-radius, while remaining outward inside the mid-radius. At the same time, a strong increase in ion-scale density fluctuations with reduced ν* is observed with BES and predicted with TGLF. On JET, perturbative transport analysis, predictive integrated modelling with JINTRAC+TGLF and non-linear and linear GENE runs all show that NBI fuelling provides an important contribution to density peaking. These results indicate that the density profiles on ITER, where NBI fuelling is very small, may be less peaked than previously thought.

AB - Dimensionless collisionality (ν*) scans with fixed density in H-mode plasmas on DIII-D and JET together with modelling have shown that the NBI fuelling plays a more important role in density peaking than found in earlier multi-machine datasets where the increased peaking at low collisionality has been primarily ascribed to turbulent effects. Perturbative gas puff modulations are performed to disentangle the fuelling and the transport effects. On DIII-D, we find that, at the lowest ν*, the pinch is directed outward and the diffusion coefficients are larger compared to higher ν* cases. With increasing ν*, the pinch becomes inward outside the mid-radius, while remaining outward inside the mid-radius. At the same time, a strong increase in ion-scale density fluctuations with reduced ν* is observed with BES and predicted with TGLF. On JET, perturbative transport analysis, predictive integrated modelling with JINTRAC+TGLF and non-linear and linear GENE runs all show that NBI fuelling provides an important contribution to density peaking. These results indicate that the density profiles on ITER, where NBI fuelling is very small, may be less peaked than previously thought.

M3 - Conference Abstract

ER -

Salmi A, Tala T, Mordijck S, Nordman H, Hughes JW. Density profile peaking on DIII-D and JET – fuelling versus transport. 2018. Abstract from 60th Annual Meeting of the APS Division of Plasma Physics, Portland, United States.