Electromagnetic ion-temperature-gradient modes and anomalous transport in a nonuniform magnetized plasma with equilibrium flows

Abstract In the nowadays and future fusion devices such as ITER and CFETR, as the use of various heating schemes, the parallel and perpendicular temperature of plasmas can be different; this temperature anisotropy may have significant effects on the turbulence. In this work, the anomalous transport driven by the ion temperature gradient instability is investigated in an anisotropic deuterium-tritium (D-T) plasma. The anisotropic factor $\alpha$, defined as the ratio of perpendicular temperature to parallel temperature, is introduced to describe the temperature anisotropy in the equilibrium distribution function of D. The linear dispersion relation in local kinetic limit is derived, and then numerically evaluated to study the dependence of mode frequency on the anisotropic factor $\alpha$ and the proportion for T particle $\vareT$ by choosing three sets of typical parameters, denoted as the cyclone base case (CBC), ITER and CFETR cases. Based on the linear results, the mixing length model approximation is adopted to analyze the quasi-linear particle and energy fluxes for D and T. It is found that choosing small $\alpha$ and large $\vareT$ is beneficial for the confinement of particle and energy for D and T. This work may be helpful for the estimation of turbulent transport level in the ITER and CFETR devices.

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Scalings of Ion-Temperature-Gradient-Driven Anomalous Transport in Tokamaks

Physical Review Letters ◽

10.1103/physrevlett.77.71 ◽

1996 ◽

Vol 77 (1) ◽

pp. 71-74 ◽

Cited By ~ 179

Author(s):

A. M. Dimits ◽

T. J. Williams ◽

J. A. Byers ◽

B. I. Cohen

Keyword(s):

Temperature Gradient ◽

Anomalous Transport ◽

Ion Temperature ◽

Ion Temperature Gradient

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Ion Temperature Gradient Mode–Driven Solitary and Shock Waves in Electron-Positron-Ion Magnetized Plasma

Brazilian Journal of Physics ◽

10.1007/s13538-020-00752-z ◽

2020 ◽

Vol 50 (4) ◽

pp. 430-437

Author(s):

Aziz Khan ◽

U. Zakir ◽

Q. Haque

Keyword(s):

Temperature Gradient ◽

Shock Waves ◽

Magnetized Plasma ◽

Ion Temperature ◽

Ion Temperature Gradient ◽

And Shock Waves ◽

Electron Positron ◽

Solitary And Shock Waves ◽

Gradient Mode

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Enstrophy non-conservation and the forward cascade of energy in two-dimensional electrostatic magnetized plasma turbulence

Journal of Plasma Physics ◽

10.1017/s0022377820000872 ◽

2020 ◽

Vol 86 (4) ◽

Author(s):

G. G. Plunk

Keyword(s):

Temperature Gradient ◽

Plasma Turbulence ◽

Magnetized Plasma ◽

Larmor Radius ◽

Ion Temperature ◽

Fluid System ◽

Ion Temperature Gradient ◽

Zonal Flows ◽

Electron Temperature Gradient ◽

Enstrophy Cascade

A fluid system is derived to describe electrostatic magnetized plasma turbulence at scales somewhat larger than the Larmor radius of a given species. It is related to the Hasegawa–Mima equation, but does not conserve enstrophy, and, as a result, exhibits a forward cascade of energy, to small scales. The inertial-range energy spectrum is argued to be shallower than a $-11/3$ power law, as compared to the $-5$ law of the Hasegawa–Mima enstrophy cascade. This property, confirmed here by direct numerical simulations of the fluid system, may help explain the fluctuation spectrum observed in gyrokinetic simulations of streamer-dominated electron-temperature-gradient driven turbulence (Plunk et al., Phys. Rev. Lett., vol. 122, 2019, 035002), and also possibly some cases of ion-temperature-gradient driven turbulence where zonal flows are suppressed (Plunk et al., Phys. Rev. Lett., vol. 118, 2017, 105002).

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