Vortex-induced vibration characteristics of harbor seal whisker under different wakes

In order to study the ability of the harbor seal whisker system to precisely perceive and identify the wakes of objects, the hydrodynamic characteristics of the whisker in the wake of different objects are analyzed: in this paper, a geometric model of seal whisker was developed based on a general geometric shape parameter equation. Subsequently, numerical simulations were conducted for the whisker model exposed to the wakes of cylindrical, square, and diamond-shaped objects at a Reynolds number of 300. The vortex-induced vibration characteristics of the whisker model and the associated flow field structures are studied in depth, focusing on the dynamic responses of the model under different wakes. The results demonstrate that the primary frequency of the cross-flow vibration of the whisker model is consistent with the vortex shedding frequency of the upstream obstacle, irrespective of the wake type. Furthermore, there are notable disparities among different wakes regarding the flow patterns between the upstream object and the downstream whisker model and the vibration features of the latter, underscoring the intricate mechanism of the harbor seal whisker to perceive and identify objects according to different wake properties.