TH / 2 - 3 1 Anomalous Diffusion in Plasma Turbulence Models
نویسندگان
چکیده
To explore the character of the underlying transport in plasma turbulence, we have followed the motion of pseudo-particle tracers during the nonlinear evolution of three-dimensional turbulence models. These calculations have been performed for three different turbulence models and are associated with resistive interchange, resistive ballooning, and ηi modes, respectively. The finite-scale Lyapunov number is used to determine the anomalous diffusion exponent. The numerical results for these three models show that the transport mechanism is superdiffusive with an anomalous diffusion exponent in the range (0.85, 0.92).
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