Line Stretching in Random Flows
arXiv:2504.17982
Abstract
How finite-sized material lines stretch in chaotic (mono-scale) and turbulent (multi-scale) flows remains a central but unresolved problem that governs mixing, transport and reaction. We show elongation is controlled by a finite-sampling process balancing ensemble and temporal averaging that is mediated by particle dispersion. These results expose the rich dynamics of line stretching and compel reassessment of experimental data and models of fluid-borne phenomena.
6 pages, 2 figures