Yasutaro Nishimura

TL;DR: In this paper, the authors studied the power-decay length of the divertor tokamak ASDEX upgrade and showed that the drift-wave dynamics in the inner divertor and the outer divertor can be modelled by a gyro-fluid code and point to the dominance of drift waves.

TL;DR: In this article, a toroidal, nonlinear, electrostatic fluid-kinetic hybrid electron model is formulated for global gyrokinetic particle simulations of driftwave turbulence in fusion plasmas.

TL;DR: A new finite element Poisson solver is developed and applied to a global gyrokinetic toroidal code (GTC) which employs the field aligned mesh and thus a logically non-rectangular grid in a general geometry to enable the implementation of advanced kinetic electron models for global electromagnetic simulations.

TL;DR: In this article, a new phenomenon has been found during the nonlinear stage of the tokamak sawtooth crash in relatively high β plasmas, where the m/n=1/1 magnetic island evolution gives rise to convection of the pressure inside the q=1 radius and builds up steep pressure gradient across the island separatrix, and thereby trigger ballooning instabilities below the threshold at the equilibrium.

TL;DR: In this paper, a Δ′-shooting code was developed to investigate tokamak plasma tearing mode stability in a cylinder and large aspect ratio toroidal geometries, neglecting toroidal mode coupling.