Snap-through dynamics of a buckled flexible filament with different edge conditions

The flow-induced snap-through dynamics of a buckled flexible filament under different edge conditions were explored using the penalty immersed boundary method. Three filament edge conditions were simulated: a simply supported leading edge and a clamped trailing edge (SC), a clamped leading edge and a simply supported trailing edge, and both edges clamped. The effects of the bending rigidity and density ratio on the energy harvesting performance were systematically examined. Two different modes were observed: an equilibrium mode and a snap-through oscillation mode. The parameter range under which the modes were observed changed depending on the edge conditions. Mode transitions, induced by an increase in transverse fluid force, occurred when the bending rigidity was low. A clamped leading edge enhanced filament stability, whereas a simply supported leading edge reduced stability. Among the three configurations, the SC case showed the highest critical bending rigidity and oscillation frequency, resulting in superior energy harvesting performance. The greater energy harvesting ability of the SC case derives from the larger deflection and the higher strain energy in this system. The strain energy in the filament with SC edges tended to concentrate in two regions of the filament: the rear part and the section near the clamped end. The SC case, coupled with low density and high rigidity, offers favorable conditions for energy harvesting purposes.