Numerical simulation of drift waves and trapped ion modes

Journal Article · Fri Jul 01 04:00:00 EDT 1994 · Physics of Plasmas; (United States)

DOI:https://doi.org/10.1063/1.870629· OSTI ID:7295779

Kingsbury, O T; Waltz, R E ^[1]

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1. General Atomics, P.O. Box 85608, San Diego, California 92186-9784 (United States)

Two-dimensional numerical simulations are used to study the interaction of trapped electron drift waves (DW) and trapped ion modes (TIM). Wave-number ([ital k]) space is divided into long and short wave regions at a poloidal wave number corresponding to the ion bounce frequency. Two field models are used to describe trapped electron drift wave dynamics at short waves and trapped ion mode dynamics for long waves. The standard case has curvature effects and collisionality. The nonlinearity that couples the two regions includes a trapped ion banana width effect analogous to finite Larmor radius (FLR) polarization drift. The principal result of this study is that the TIM do not contribute to the diffusion significantly, regardless of the model for the nonlinear coupling to the DW. This conclusion is supported by a more general four field model that includes pressure dynamics and which allows ion temperature gradient (ITG) driven drift modes. When the collisionality is varied, the diffusion deviates from the [gamma]/[ital k][sup 2][sub [ital x]] form and tends to vanish towards the collisionless limit even though the system is strongly unstable linearly.

• DOE Contract Number: FG03-92ER54150
• OSTI ID: 7295779
• Journal Information: Physics of Plasmas; (United States), Journal Name: Physics of Plasmas; (United States) Vol. 1:7; ISSN PHPAEN; ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700330 -- Plasma Kinetics
Transport
& Impurities-- (1992-)
700340* -- Plasma Waves
Oscillations
& Instabilities-- (1992-)
CLOSED PLASMA DEVICES
COLLISIONAL PLASMA
DIFFUSION
ELECTRONS
ELEMENTARY PARTICLES
FERMIONS
LEPTONS
NUMERICAL SOLUTION
PLASMA
PLASMA DRIFT
PLASMA SIMULATION
SIMULATION
THERMONUCLEAR DEVICES
TOKAMAK DEVICES
TRANSPORT THEORY
TRAPPED ELECTRONS
TURBULENCE