Open AccessEffect of collisionality on the microinstabilities in the Globus-M spherical tokamak
Author(s) -
Е. О. Киселев,
Н. Н. Бахарев,
V. V. Bulanin,
V. K. Gusev,
Н. А. Хромов,
Г. С. Курскиев,
В. Б. Минаев,
I. V. Miroshnikov,
M. I. Patrov,
А. В. Петров,
Yu. V. Petrov,
Н. В. Сахаров,
P. B. Schegolev,
A. Yu. Telnova,
В. А. Токарев,
S.Yu. Tolstyakov,
E. A. Tukhmeneva,
A. Yu. Yashin
Publication year - 2019
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/1383/1/012003
Subject(s) - collisionality , collision frequency , tokamak , spherical tokamak , gyroradius , instability , physics , atomic physics , scaling , plasma , magnetic field , radius , computational physics , nuclear physics , mechanics , geometry , computer science , mathematics , computer security , quantum mechanics
Simulations of the microtearing instability developing in plasma of the Globus-M spherical tokamak were performed using the GENE gyrokinetic code in the flux-tube linear approximation mode. Under the effect of the instability, the magnetic islands form on the scale of the ion Larmor radius, and the magnetic field fluctuations occur that generate electron heat fluxes. The ion heat fluxes as well as the fluxes associated with the electrostatic fluctuations are negligible. The maximum growth rate of the microtearing instability is reached at a collision frequency within the experimental range of the collision frequency variation, within which the B T × τ E ∝ ν* −0.4±0.1 scaling calculations were performed [1]. In similar calculations performed at the MAST tokamak, the growth rate decreases with decreasing collisionality in the entire range of the collision frequency variation, within which the B T × τ E ∝ ν* −0.82 scaling calculations were performed [2]. This can explain why the dependences of energy confinement time on the collision frequency obtained for the MAST&NSTX and the Globus-M tokamaks are different.