Flutter instability in an internal flow energy harvester

Vibration-based flow energy harvesting enables robust, in-situ extraction for low-power applications, such as distributed sensor networks. Fluid-structure instabilities dictate a harvester's viability since the structural response to determines its power output. Previous work on flextensional-based harvester demonstrated that an elastic member within converging-diverging channel is susceptible aeroelastic flutter. This explores mechanism driving flutter through experiments and simulations. A model then developed based flow-rate modulation considering effects of both normal spanwise confinement instability. Linear stability analysis replicates onset, critical frequency, mode shapes observed in experiments. The suggests throat principal fluid-induced vibration. generalized presented can serve foundation design parameter exploration harvesters, perhaps leading more powerful devices future, but also other similar geometries where instability arises narrow passage.