Exponentially mixing flows with slow enhanced dissipation

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Cooperman, William, Iyer, Gautam, Rowan, Keefer, Son, Seungjae
Natura: Preprint
Pubblicazione: 2025
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866912510540513280
author Cooperman, William
Iyer, Gautam
Rowan, Keefer
Son, Seungjae
author_facet Cooperman, William
Iyer, Gautam
Rowan, Keefer
Son, Seungjae
contents Consider a passive scalar which is advected by an incompressible flow $u$ and has small molecular diffusivity $κ$. Previous results show that if $u$ is exponentially mixing and $C^1$, then the dissipation time is $O(|\log κ|^2)$. We produce a family of incompressible flows which are $C^0$ and exponentially mixing, uniformly in $κ$; however have a dissipation time of order $1/κ$ (i.e. exhibits no enhanced dissipation). We also estimate the dissipation time of mixing flows, and obtain improved bounds in terms of the mixing rate with explicit constants, and allow for a time inhomogeneous mixing rate which is typical for random constructions of mixing flows.
format Preprint
id arxiv_https___arxiv_org_abs_2507_21305
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Exponentially mixing flows with slow enhanced dissipation
Cooperman, William
Iyer, Gautam
Rowan, Keefer
Son, Seungjae
Probability
Analysis of PDEs
Dynamical Systems
60J25, 35Q49, 76R05
Consider a passive scalar which is advected by an incompressible flow $u$ and has small molecular diffusivity $κ$. Previous results show that if $u$ is exponentially mixing and $C^1$, then the dissipation time is $O(|\log κ|^2)$. We produce a family of incompressible flows which are $C^0$ and exponentially mixing, uniformly in $κ$; however have a dissipation time of order $1/κ$ (i.e. exhibits no enhanced dissipation). We also estimate the dissipation time of mixing flows, and obtain improved bounds in terms of the mixing rate with explicit constants, and allow for a time inhomogeneous mixing rate which is typical for random constructions of mixing flows.
title Exponentially mixing flows with slow enhanced dissipation
topic Probability
Analysis of PDEs
Dynamical Systems
60J25, 35Q49, 76R05
url https://arxiv.org/abs/2507.21305