Search for deterministic chaos in ELM time series of ASDEX upgrade Tokamak

Author

Ikonen, Timo M J ; Dumbrajs, Olgierd

Author_Institution

Dept. of Eng. Phys. & Math., Helsinki Univ. of Technol., Finland

Volume

33

Issue

3

fYear

2005

fDate

6/1/2005 12:00:00 AM

Firstpage

1115

Lastpage

1122

Abstract

Time intervals between edge localized modes (ELMs) from Asdex Upgrade tokamak have been analyzed to determine whether ELM dynamics is chaotic (deterministic) or random (noise-dominated). Both linear and nonlinear prediction methods have been used, Hurst and Lyapunov exponents evaluated, and block entropy analysis performed. No concluding evidence of presence of deterministic chaos has been found. New measurements of significantly longer ELM time series are required to improve the quality of the analysis.

Keywords

Tokamak devices; chaos; entropy; plasma boundary layers; plasma instability; plasma nonlinear processes; plasma thermodynamics; plasma toroidal confinement; ASDEX Upgrade tokamak; Hurst exponent; Lyapunov exponent; block entropy; chaos; edge localized modes; Chaos; Current density; Magnetohydrodynamics; Physics; Plasma confinement; Plasma density; Plasma properties; Plasma transport processes; Tokamaks; Variable speed drives; Block entropy; chaos; edge localized modes; nonlinear dynamics;

fLanguage

English

Journal_Title

Plasma Science, IEEE Transactions on

Publisher

ieee

ISSN

0093-3813

Type

jour

DOI

10.1109/TPS.2005.848599

Filename

1440550