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arXiv · 1904.12886

CHNS: A case study of turbulence in elastic media

Xiang Fan·P. H. Diamond·L. Chacón
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Abstract

Recent progress in the study of Cahn-Hilliard Navier-Stokes (CHNS) turbulence is summarized. This is an example of \textit{elastic turbulence}, which can occur in elastic (i.e. self-restoring) media. Such media exhibit memory due freezing-in laws, as does MHD, which in turn constrains the dynamics. We report new results in the theory of CHNS turbulence in 2D, with special emphasis on the role of structure (i.e. `blob') formation and its interaction with the dual cascade. The evolution of a concentration gradient in response to a single eddy -- analogous to flux expulsion in MHD -- is analyzed. Lessons learned are discussed in the context of MHD and other elastic media.

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Xiang Fan, P. H. Diamond, L. Chacón. 2019-04-29. CHNS: A case study of turbulence in elastic media. https://doi.org/10.1063/1.5016075

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