Plasma and Fusion Research

Volume 19, 1201035 (2024)

Rapid Communications

Hierarchical Clustering of Modes in Numerical Turbulence Fields
Akifumi OKUNO1,2), Takumi KODAHARA3), Makoto SASAKI3,4)
1)
The Institute of Statistical Mathematics, Tachikawa 190-0014, Japan
2)
RIKEN Center for Advanced Intelligence Project, Nihon-bashi 103-0027, Japan
3)
College of Industrial Technology, Nihon University, Narashino 274-0072, Japan
4)
Research Center for Plasma Turbulence, Kyushu University, Kasuga 816-8580, Japan
(Received 29 September 2024 / Accepted 9 October 2024 / Published 26 December 2024)

Abstract

We propose an automated method for decomposing turbulence, where the modes are derived by applying singular value decomposition to the electrostatic potential field in turbulence simulations. After classifying the modes into zonal flows and turbulence based on azimuthal integration, the turbulence is further decomposed into finer components through hierarchical clustering. This approach systematically breaks down the turbulence into hierarchical levels, providing flexible control over the degrees of freedom in the mode decomposition process.

Keywords

turbulence, electrostatic potential field, data-driven approach, clustering

DOI: 10.1585/pfr.19.1201035

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