Search Results - "WAKATANI, Masahiro"

Self-organization of electrostatic turbulence in a cylindrical plasma by Hasegawa, A, Wakatani, M

“…On the basis of theory and computer simulations the authors show that electrostatic turbulence in a cylindrical plasma with magnetic shear and curvature…”
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Nonlinear double tearing mode in negative shear cylindrical tokamaks by SATO, Masahiko, HAMAGUCHI, Satoshi, WAKATANI, Masahiro

“…For negative shear cylindrical tokamaks, nonlinear behavior of double tearing modes (DTMs) with (m,n)=(3,1), (2,1) and (1,1) has been studied for 0.9<qmin<3,…”
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Plasma current effects on unstable resistive drift-Alfvén modes in a magnetized cylindrical plasma by MIYATO, Naoaki, HAMAGUCHI, Satoshi, WAKATANI, Masahiro

“…In a currentless plasma, there are many unstable drift-Alfvén modes with different radial eigenfunctions with fixed poloidal and toroidal mode numbers, m and…”
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Damping of surface Alfvén wave in a slab plasma by TATSUNO, T, WAKATANI, M

“…The MHD wave is studied when two steep density gradient regions exist at surfaces of slab plasma.In such a case, it is shown that the surface Alfvén wave has…”
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Simulation study on the motion of the pressure perturbation in an axisymmetric toroidal system by AIBA, Nobuyuki, TOKUDA, Shinji, HAYASHI, Takaya, WAKATANI, Masahiro

“…In tokamaks, it is observed that an ablated and ionized pellet moves toward the low field side of the torus. This phenomenon can be considered as the…”
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Comparison between Double-Resonant and Non-Resonant Mode Driven Convections in a Stellarator with a Non-Monotonic Rotational Transform by UNEMURA, Takeshi, HAMAGUCHI, Satoshi, WAKATANI, Masahiro

“…For a stellarator (or tokamak) with a non-monotonic rotational transform, both the double-resonant and non-resonant interchange type modes become unstable,…”
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Resistive drift-Alfvén instability in a cylindrical plasma by MIYATO, N, HAMAGUCHI, S, WAKATANI, M

“…Linearized eigenmode equations governing resistive drift-Alfvén modes are derived by using the two-fluid model for a cylindrical plasma with a uniform…”
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Stabilization of resistive wall mode due to shear Alfvén resonance in a cylindrical plasma with a uniform longitudinal flow by YOSHIOKA, A, TATSUNO, T, WAKATANI, M

“…Resistive wall mode (RWM) is studied in a cylindrical plasmawith a uniform longitudinal plasma flow.In order to simplify the analysis, two steps current…”
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Nonlinear interchange mode in edge plasma with poloidal shear flow by TAKAYAMA, A, WAKATANI, M, SUGAMA, H

“…Nonlinear evolution of two dimensional pressure-driven interchange mode produces relaxation oscillations in the presence of poloidal shear flow for Reyleigh…”
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Study of two-dimensional interchange turbulence by SUGAMA, H, WAKATANI, M

“…An eddy viscosity model describing enstrophy transfer in two-dimensional turbulence is presented. It is similar to that of Canuto et al. [Phys. Fluids 30…”
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Statistical analysis of anomalous transport in resistive interchange turbulence by SUGAMA, H, WAKATANI, M

“…A new anomalous transport model for resisistive interchange turbulence is derived from statistical analysis applying two-scale direct-interaction approximation…”
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Hexapole Field Effects on Currentless MHD Equilibrium and Stability of l =2 Heliotron/Torsatron by Matsumoto, Taro, Nakamura, Yuji, Wakatani, Masahiro

“…Averaged flux surfaces with respect to the toroidal angle in l=2 heliotron/torsatrons are deformed in D-shape or inverse D-shape by the hexapole field. D-shape…”
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A transport study for resistive interchange mode turbulence based on a renormalized theory by SUGAMA, H, WAKATANI, M

“…A new formulation of renormalized theory for fluid-type turbulence to obtain wavenumber spectrum and turbulent diffusivity is presented. An application to the…”
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Study of MHD Equilibrium and Stability for Heliotron/Torsatron with Helical Axis by MATSUMOTO, T, NAKAMURA, Y, WAKATANI, M

“…MHD equilibrium and stability of LHD (Large HelicalDevice) are studied when circular plane magnetic axis is distortedinto spatial helical one by introducing…”
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Nonlinear evolution of q=1 triple tearing modes in a tokamak plasma by Bierwage, Andreas, Hamaguchi, Satoshi, Wakatani, Masahiro, Benkadda, Sadruddin, Leoncini, Xavier

“…In magnetic configurations with two or three q=1 (with q being the safety factor) resonant surfaces in a tokamak plasma, resistive magnetohydrodynamic modes…”
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Vlasov Equation in the Stochastic Magnetic Field by Sugama, Hideo, Okamoto, Masao, Wakatani, Masahiro

“…We investigate the Vlasov equation in the stochastic magnetic field as a stochastic Liouville equation and derive the equation for the ensemble-averaged…”
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Trapped Particle Confinement Studies in l =2 Torsatrons for Additional Helical Coils, Radial Electric Field and Finite Beta Effect by Kato, Akira, Nakamura, Yuji, Wakatani, Masahiro

“…l=2 torsatrons are studied to improve the high energy trapped particle confinement with additional l=1 and/or l=3 helical coils. The winding laws are selected…”
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Transport study for radial electric field and poloidal ion flow in heliotron E by WATANABE, K, NAKAMURA, Y, WAKATANI, M

“…Radial electric field, Er, is obtained by imposing the ambipolar condition or solving the electric field diffusion equation in the transport code for Heliotron…”
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Relation between growth rate of the Suydam mode and that of low mode number interchange instability by SUGAMA, H, WAKATANI, M

“…Pressure-driven interchange instability of any mode number with the same helicity has the same limiting beta value as that by the Suydam criterion in the…”
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Stabilization effect of parallel heat conductivity on g mode by YAGI, M, WAKATANI, M

“…The effect of parallel heat conductivity κ// on g mode is studied analytically. Under electrostatic approximation, growth rate γ is reduced according to…”
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