G. M. Staebler E. Belli J. Candy J. E. Kinsey H. Dudding B. Patel
The verification and calibration of a new quasi-linear transport model with a large database of gyrokinetic turbulence simulations is presented in this paper. In a previous paper [1], a model for the saturated spectrum of electric potential fluctuations was developed based on the properties of the non-linear 3D spectrum. In this paper, a modifi…
PreprintG. M. Staebler J. Candy E. Belli J. E. Kinsey N. Bonanomi B. Patel
The findings of an investigation into the properties of the three dimensional (3D) saturated fluctuation intensity of the electric potential in gyrokinetic turbulence simulations is presented. Scans in flux surface elongation and Shafranov shift are used to isolate the tokamak geometric dependencies. The potential intensity required in order to …
Preprint PublishedS. Breton F.J. Casson C. Bourdelle J. Citrin Y. Baranov Y. Camenen C. Challis J. Garcia G. Corrigan L. Garzotti S. Henderson F. Koechl M. OMullane T. Puetterich M. Sertoli M. Valisa JET contributors
For the first time, over five confinement times, the self-consistent flux driven time evolution of heat, momentum transport and particle fluxes of electrons and multiple ions including Tungsten (W) is modeled within the integrated modeling platform JETTO [Romanelli M et al PFR 2014], using first principle-based codes : namely, QuaLiKiz [Bourd…
Preprint PublishedS. Breton F.J. Casson C. Bourdelle C. Angioni E. Belli Y. Camenen J. Citrin X. Garbet Y. Sarazin The JET contributors
Heavy impurities, such as tungsten (W), can exhibit strongly poloidally asymmetric density profiles in rotating or radio frequency heated plasmas. In the metallic environment of JET, the poloidal asymmetry of tungsten enhances its neoclassical transport up to an order of magnitude, so that neoclassical convection is expected to dominate over turbul…
PreprintA.G. Peeters F. Rath R. Buchholz Y. Camenen J. Candy F.J. Casson S.R. Grosshauser W.A. Hornsby D. Strintzi A. Weikl
It is shown that ITG turbulence close to the threshold exhibits a long time behaviour, with smaller heat fluxes at later times. This reduction is connected with the slow growth of long wave length zonal flows and, consequently, the numerical dissipation on these flows must be sufficient small. Close to the nonlinear threshold for turbulence generat…
Preprint PublishedR. V. Bravenec J. Candy M. Barnes C. Holland
Verification of nonlinear microstability codes is a necessary step before comparisons or predictions of turbulent transport in toroidal devices can be justified. By verification we mean demonstrating that a code correctly solves the mathematical model upon which it is based. Some degree of verification can be accomplished indirectly from analytical…
PublishedI. Pusztai T. Fülöp J. Candy R. J. Hastie
The stability of ion temperature gradient ITG modes and the quasilinear fluxes driven by them are analyzed in weakly collisional tokamak plasmas using a semianalytical model based on an approximate solution of the gyrokinetic equation, where collisions are modeled by a Lorentz operator. Although the frequencies and growth rates of ITG modes far fro…
Published