Understanding Plasma Turbulence Through Exact Coherent Structures

Sidney D. V. Williams; Matthew N. Gudorf; Dmitri M. Orlov

doi:10.1063/5.0282368

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arXiv · 2505.19363

Understanding Plasma Turbulence Through Exact Coherent Structures

Sidney D. V. Williams·Matthew N. Gudorf·Dmitri M. Orlov

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Abstract

Plasma turbulence is a key challenge in understanding transport phenomena in magnetically confined plasmas. This work presents a novel approach using periodic orbit theory to analyze plasma turbulence, identifying fundamental structures that underpin chaotic motion. By applying numerical optimization techniques to the Kuramoto-Sivashinsky equation - a reduced model for drift-wave-driven trapped particle turbulence - we extract coherent spacetime patterns that serve as building blocks of turbulent dynamics. These structures provide a framework to systematically describe turbulence as a composition of recurrent solutions, revealing an underlying order within chaotic plasma motion. Our findings suggest that multi-periodic orbit theory can be effectively applied to spatiotemporal turbulence, offering a new method for predicting and potentially controlling transport processes in fusion plasmas. This study provides a bridge between nonlinear dynamical systems theory and plasma physics, highlighting the relevance of periodic orbit approaches for understanding complex plasma behavior.

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Sidney D. V. Williams, Matthew N. Gudorf, Dmitri M. Orlov. 2025-05-25. Understanding Plasma Turbulence Through Exact Coherent Structures. https://doi.org/10.1063/5.0282368

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