The hard membrane process and transport barriers of turbulent flows

Olga Aryasova; Franco Flandoli; Andrey Pilipenko

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arXiv · 2510.16456

The hard membrane process and transport barriers of turbulent flows

Olga Aryasova·Franco Flandoli·Andrey Pilipenko

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Abstract

Motivated by the phenomenon of transport barriers in fusion plasma devices, we write a mathematical model of heat dispersion in a turbulent fluid with a transport barrier, properly idealized; in a scaling limit of the turbulence model with separation of scales we get a heat equation with space-dependent diffusion coefficient, poorly diffusing near the barrier; then we investigate the scaling limit when the diffused barrier converges to a sharp separating surface and describe the limit by means of the stochastic process called Brownian motion with hard membrane.

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Olga Aryasova, Franco Flandoli, Andrey Pilipenko. 2025-10-18. The hard membrane process and transport barriers of turbulent flows. https://arxiv.org/abs/2510.16456

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