Lagrangian transport in the time-periodic two-dimensional lid-driven square cavity

The Lagrangian transport in the laminar incompressible flow a two-dimensional square cavity driven by harmonic tangential oscillation of lid is investigated numerically for wide range Reynolds and Strouhal numbers. topology fluid trajectories analyzed stroboscopic projections revealing co-existence chaotic regular Kolmogorov–Arnold–Moser (KAM) tori. pathline structure strongly depends on number frequency lid. Typically, most pathlines are when small, with few KAM tori being stretched along instantaneous streamlines flow. As increased, motion becomes more size grows until, at high frequencies, they resemble mean