Calculations of lower hybrid current drive in ITER

Decker, J.; Peysson, Y.; Hillairet, J.; Artaud, J.F.; Basiuk, V.; Bécoulet, A.; Ekedahl, A.; Goniche, M.; Hoang, G. T.; Imbeaux, F.; Ram, A. K.; Schneider, M.

doi:10.1088/0029-5515/51/7/073025

Cited by 63 publications

(69 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We have applied the above theory to calculate the QL power deposition profile for DEMO in flat and peaked density profiles with the two kinds of electron temperature profiles, as established in Ref. [16], while we have limited the study on ITER for the the steady-state scenario of ITER [17] called Scenario 4. The LH power deposition profiles has been accounted by studying the effect of the wave spectrum on the deposition layer, in particular the width of the spectrum and the strength of the admissible electric field surface density expressed in kW/cm 2 (for the LH <10kW/cm 2 ).…”

Section: Numerical Results For Demo and Itermentioning

confidence: 99%

Quasi-linear modeling of lower hybrid current drive in ITER and DEMO

Cardinali¹,

Cesario²,

Panaccione³

et al. 2015

AIP Conference Proceedings

View full text Add to dashboard Cite

Abstract. First pass absorption of the Lower Hybrid waves in thermonuclear devices like ITER and DEMO is modeled by coupling the ray tracing equations with the quasi-linear evolution of the electron distribution function in 2D velocity space. As usually assumed, the Lower Hybrid Current Drive is not effective in a plasma of a tokamak fusion reactor, owing to the accessibility condition which, depending on the density, restricts the parallel wavenumber to values greater than n ||crit and, at the same time, to the high electron temperature that would enhance the wave absorption and then restricts the RF power deposition to the very periphery of the plasma column (near the separatrix). In this work, by extensively using the "ray star " code, a parametric study of the propagation and absorption of the LH wave as function of the coupled wave spectrum (as its width, and peak value), has been performed very accurately. Such a careful investigation aims at controlling the power deposition layer possibly in the external half radius of the plasma, thus providing a valuable aid to the solution of how to control the plasma current profile in a toroidal magnetic configuration, and how to help the suppression of MHD mode that can develop in the outer part of the plasma. This analysis is useful not only for exploring the possibility of profile control of a pulsed operation reactor as well as the tearing mode stabilization, but also in order to reconsider the feasibility of steady state regime for DEMO.

show abstract

Section: Numerical Results For Demo and Itermentioning

confidence: 99%

Quasi-linear modeling of lower hybrid current drive in ITER and DEMO

Cardinali¹,

Cesario²,

Panaccione³

et al. 2015

AIP Conference Proceedings

View full text Add to dashboard Cite

show abstract

“…An adaptive-real time controlled RF antenna may also provide an effective method for bringing down the plasma current rapidly when the signatures of a disruption are detected. Typical lower hybrid spectra and current drive efficiencies are estimated for the ITER plasma in Decker et al [1]. The launched RF waves have wavelengths of 6 cm with electric field of a few times 10 2 kV/m and associated magnetic fields of a few mT.…”

Section: Lower Hybrid Current Drive In Turbulencementioning

confidence: 99%

“…The slow wave is quasi-electrostatic with a low perpendicular phase velocity. Depending on the ITER plasma conditions, this branch is expected to drive current somewhere between r/a=0.7 and the separatrix [1]. The antenna also couples to the fast wave eigenmode with a higher perpendicular phase velocity in the low density plasma.…”

Section: Lower Hybrid Current Drive In Turbulencementioning

confidence: 99%

Penetration and scattering of lower hybrid waves by density fluctuations

Horton¹,

Goniche²,

Peysson³

et al. 2014

AIP Conference Proceedings

Self Cite

View full text Add to dashboard Cite

show abstract

“…The E z field of fast waves is usually lower than that of slow wave, but it increases with the driving frequency increase and it becomes comparable to that of slow wave in the frequency range of ω ≥ 2ω lh . Concering the difference of absorption and current drive between LHSW and LHFW, it was already simulated for ITER LHCD study [13] and for the identification of the role of mode converted FW in LHCD [14]. And it was found that LHFW current drive can be as efficient as LHSW.…”

Section: Absorption and Current Drivementioning

confidence: 99%

A current drive by using the fast wave in frequency range higher than two timeslower hybrid resonance frequency on tokamaks

et al. 2017

View full text Add to dashboard Cite

Abstract.An efficient current drive scheme in central or off-axis region is required for the steady state operation of tokamak fusion reactors. The current drive by using the fast wave in frequency range higher than two times lower hybrid resonance (w>2wlh) could be such a scheme in high density, high temperature reactor-grade tokamak plasmas. First, it has relatively higher parallel electric field to the magnetic field favorable to the current generation, compared to fast waves in other frequency range. Second, it can deeply penetrate into high density plasmas compared to the slow wave in the same frequency range. Third, parasitic coupling to the slow wave can contribute also to the current drive avoiding parametric instability, thermal mode conversion and ion heating occured in the frequency range w<2wlh. In this study, the propagation boundary, accessibility, and the energy flow of the fast wave are given via cold dispersion relation and group velocity. The power absorption and current drive efficiency are discussed qualitatively through the hot dispersion relation and the polarization. Finally, those characteristics are confirmed with ray tracing code GENRAY for the KSTAR plasmas.

show abstract

Calculations of lower hybrid current drive in ITER

Cited by 63 publications

References 41 publications

Quasi-linear modeling of lower hybrid current drive in ITER and DEMO

Quasi-linear modeling of lower hybrid current drive in ITER and DEMO

Penetration and scattering of lower hybrid waves by density fluctuations

A current drive by using the fast wave in frequency range higher than two timeslower hybrid resonance frequency on tokamaks

Contact Info

Product

Resources

About