Wake Dynamics of Permeable Disks across the Transition from Steady to Chaotic Flow - Dataset

Dataset corresponds to the manuscript - Wake Dynamics of Permeable Disks across the Transition from Steady to Chaotic Flow. The manuscript abstract states: We numerically investigate the steady and unsteady wake of three-dimensional permeable disks over a Reynolds number (Re) range of 100– 300 and a Darcy number (Da) range of 10-9–10-3. For disks with low permeability (Da ≤ 8 ×10-5), the dynamical transition route is the same as that of impervious disks, with the critical Re for all bifurcations increasing with decreasing permeability. In contrast, for disks with high permeability (Da ≥ 2×10-4), all unsteady bifurcations are suppressed and the wake remains in a steady regime throughout the Re range considered. Interestingly, at moderate Da, permeability gives rise to two previously unreported flow regimes. The first one is the `SVR breathing' regime, occurring at Da≅10-4 and Re≅200, and is attributed to the subharmonic lock-in between two distinct unsteady dynamics: the shedding of hairpin vortices and the low frequency unsteadiness of the near wake recirculation regions. The second one is the `intermittency' regime, which occurs at Da≅1.5×10-4, Re≅200; the wake alternates irregularly between two periodic modes with orthogonal planes of symmetry. Future work might include verifying whether intermittency arises from the energy competition between two modes, as the vortices lack sufficient energy to sustain stable single-mode harmonic oscillations. These findings demonstrate that permeability can fundamentally alter wake dynamics and introduce new wake structures that do not occur on an impervious disk.