Dynamics of the LH-transition in TUMAN-3M tokamak in the scenarios with cryogenic pellet injection

Research output: Contribution to journalArticleScientificpeer-review

Researchers

Research units

  • Ioffe Inst, St. Petersburg Scientific Centre of the Russian Academy of Sciences, Ioffe Physical Technical Institute, Russian Academy of Sciences

Abstract

In the experiments on tangential fuel pellet injection in the TUMAN-3M tokamak an initiation of LH-transition or, in several scenarios-temporal (1-2 ms) confinement improvement with the following backwards transition was observed. To understand the possibility of the transitions, a model calculating the evolution of density and ion temperature profiles under the effect of source profile perturbation and plasma cooling created by pellet evaporation was developed. In the model, a diffusion coefficient depending on radial electric field shear value was used. Turbulence parameters are defined using a gyrokinetic simulation of the experiments with ELMFIRE code. Modeling results are in good agreement with experiments. Using the data obtained from the modeling, non-linear particle flux dependency on density gradient was analyzed; the existence of two stabile solutions for two confinement modes dependent on particle flux value was proved, in agreement with experiments.

Details

Original languageEnglish
Article number112007
Number of pages9
JournalNuclear Fusion
Volume58
Issue number11
Publication statusPublished - Nov 2018
MoE publication typeA1 Journal article-refereed

    Research areas

  • tokamak, LH-transition, pellet injection, turbulence, radial electric field, H-MODE, TRANSPORT BARRIERS, POLOIDAL ROTATION, PLASMAS, SIMULATIONS

ID: 31444681