Role of NBI fuelling in contributing to density peaking between the ICRH and NBI identity plasmas on JET
Artikel i vetenskaplig tidskrift, 2022

Density peaking has been studied between an ICRH and NBI identity plasma in JET. The comparison shows that 8 MW of NBI heating/fueling increases the density peaking by a factor of two, being R/L (n) = 0.45 for the ICRH pulse and R/L (n) = 0.93 for the NBI one averaged radially over rho (tor) = 0.4, 0.8. The dimensionless profiles of q, rho *, upsilon *, beta (n) and T (i)/T (e) approximate to 1 were matched within 5% difference except in the central part of the plasma (rho (tor) < 0.3). The difference in the curvature pinch (same q-profile) and thermo-pinch (T (i) = T (e)) between the ICRH and NBI discharges is virtually zero. Both the gyro-kinetic simulations and integrated modelling strongly support the experimental result where the NBI fuelling is the main contributor to the density peaking for this identity pair. It is to be noted here that the integrated modeling does not reproduce the measured electron density profiles, but approximately reproduces the difference in the density profiles between the ICRH and NBI discharge. Based on these modelling results and the analyses, the differences between the two pulses in impurities, fast ions (FIs), toroidal rotation and radiation do not cause any such changes in the background transport that would invalidate the experimental result where the NBI fuelling is the main contributor to the density peaking. This result of R/L (n) increasing by a factor of 2 per 8 MW of NBI power is valid for the ion temperature gradient dominated low power H-mode plasmas. However, some of the physics processes influencing particle transport, like rotation, turbulence and FI content scale with power, and therefore, the simple scaling on the role of the NBI fuelling in JET is not necessarily the same under higher power conditions or in larger devices.

particle transport modelling

NBI fuelling

dimensioness identity plasma

density peaking

particle transport

Författare

T. Tala

Teknologian Tutkimuskeskus (VTT)

F. Eriksson

Culham Science Centre

P. Mantica

Consiglio Nazionale delle Ricerche (CNR)

A. Mariani

Universita' degli Studi di Milano-Bicocca

A. Salmi

Teknologian Tutkimuskeskus (VTT)

E. R. Solano

Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas (Ciemat)

I. S. Carvalho

Universidade de Lisboa

A. Chomiczewska

Institute of Plasma Physics & Laser Microfusion (IPPLM)

E. Delabie

Culham Science Centre

J. Ferreira

Universidade de Lisboa

Emil Fransson

Chalmers, Rymd-, geo- och miljövetenskap, Astronomi och plasmafysik, Astronomi och plasmafysik 2

L. Horvath

Culham Science Centre

P. Jacquet

Culham Science Centre

D. King

Culham Science Centre

A. Kirjasuo

Teknologian Tutkimuskeskus (VTT)

S. Leerink

Aalto-Yliopisto

E. Lerche

TEC Partner

C. Maggi

Culham Science Centre

M. Marin

Dutch Institute for Fundamental Energy Research (DIFFER)

M. Maslov

Culham Science Centre

S. Menmuir

Culham Science Centre

R. B. Morales

Culham Science Centre

V Naulin

Danmarks Tekniske Universitet (DTU)

M. F. F. Nave

Universidade de Lisboa

Hans Nordman

Chalmers, Rymd-, geo- och miljövetenskap, Astronomi och plasmafysik

C. Perez von Thun

Institute of Plasma Physics & Laser Microfusion (IPPLM)

P. A. Schneider

Max-Planck-Gesellschaft

M. Sertoli

Tokamak Energy Ltd

K. Tanaka

National Institutes of Natural Sciences

Nuclear Fusion

0029-5515 (ISSN)

Vol. 62 6 066008

Implementation of activities described in the Roadmap to Fusion during Horizon 2020 through a Joint programme of the members of the EUROfusion consortium (EUROfusion)

Europeiska kommissionen (EU) (EC/H2020/633053), 2014-01-01 -- 2019-01-01.

Ämneskategorier

Energiteknik

Annan fysik

Fusion, plasma och rymdfysik

DOI

10.1088/1741-4326/ac5667

Mer information

Senast uppdaterat

2022-04-19