Michele Coti Zelati, Augusto Del Zotto, Klaus Widmayer
{"title":"Stability of Viscous Three-Dimensional Stratified Couette Flow via Dispersion and Mixing","authors":"Michele Coti Zelati, Augusto Del Zotto, Klaus Widmayer","doi":"10.1002/cpa.70048","DOIUrl":null,"url":null,"abstract":"<p>This article explores the stability of stratified Couette flow in the viscous <span></span><math>\n <semantics>\n <mrow>\n <mn>3</mn>\n <mi>d</mi>\n </mrow>\n <annotation>$3d$</annotation>\n </semantics></math> Boussinesq equations. In this system, mixing effects arise from the shearing background, and gravity acts as a restoring force leading to dispersive internal gravity waves. These mechanisms are of fundamentally different nature and relevant in complementary dynamical regimes. Our study combines them to establish a bound for the non-linear transition threshold, which is quantitatively larger than the inverse Reynolds number <span></span><math>\n <semantics>\n <mi>ν</mi>\n <annotation>$\\nu$</annotation>\n </semantics></math>, and increases with stronger stratification resp. gravity.</p>","PeriodicalId":10601,"journal":{"name":"Communications on Pure and Applied Mathematics","volume":"79 12","pages":"2435-2490"},"PeriodicalIF":3.5000,"publicationDate":"2026-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cpa.70048","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Communications on Pure and Applied Mathematics","FirstCategoryId":"100","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1002/cpa.70048","RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2026/4/24 0:00:00","PubModel":"Epub","JCR":"Q1","JCRName":"MATHEMATICS","Score":null,"Total":0}
引用次数: 0
Abstract
This article explores the stability of stratified Couette flow in the viscous Boussinesq equations. In this system, mixing effects arise from the shearing background, and gravity acts as a restoring force leading to dispersive internal gravity waves. These mechanisms are of fundamentally different nature and relevant in complementary dynamical regimes. Our study combines them to establish a bound for the non-linear transition threshold, which is quantitatively larger than the inverse Reynolds number , and increases with stronger stratification resp. gravity.