Research on the vortex dynamics of two-dimensional jellyfish-like flapping wings based on particle image velocimetry

As a new type of micro aircraft configuration, the jellyfish-like flying aircraft has the advantages of low noise and flexible maneuvering, which has attracted the attention of the academic community. In this paper, a pair of two-dimensional plates rotating around fixed axes is used as a simplified model of jellyfish-like flapping wings. The disturbed flow fields in static water are measured by the time-resolved particle image velocimetry. By controlling the frequency and angular amplitude of the flapping motion, the influence of the motion parameters on the vortex characteristics and evolution law is studied. The vortex generation, shedding, and interaction processes are analyzed by using the phase average method and the circulation tracking technique. The forming mechanism of thrust is explained from the perspective of vortex dynamics. The experimental results provide certain references for the design of the jellyfish-like flying machines.