Dissipation enhancing properties for a class of Hamiltonian flows with closed streamlines

• Published in: Communications in partial differential equations Vol. 50; no. 3; pp. 301 - 352
• Main Authors: Dolce, Michele, Johansson, Carl Johan Peter, Sorella, Massimo
• Format: Journal Article
• Language: English
• Published: Philadelphia Taylor & Francis 04.03.2025; Taylor & Francis Ltd
• Subjects: Asymptotic series; Domains; Enhanced dissipation; Hamiltonian flows; Hamiltonian functions; Molecular diffusion; Passive scalar; Peclet number; Radial flow; Velocity distribution
• ISSN: 0360-5302; 1532-4133
• DOI: 10.1080/03605302.2024.2447497

We study the evolution of a passive scalar subject to molecular diffusion and advected by an incompressible velocity field on a 2D bounded domain. The velocity field is u = ∇ ⊥ H , where H is an autonomous Hamiltonian whose level sets are Jordan curves foliating the domain. We focus on the high Pécl...