Meeting Abstract

68.3  Thursday, Jan. 6  A numerical investigation of the hydrodynamic signature of batoid swimming PEDERZANI, Jean-Noel*; MOORED, Keith; FISH, Frank; HAJ-HARIRI, Hossein; University of Virginia; University of Virginia; West Chester University; University of Virginia hh2b@virginia.edu

The different batoid species use different modes of swimming to propel themselves in water. To evaluate hydrodynamic differences between these swimming modes a computational fluid dynamic model can be employed. A mixed Lagrangian-Eulerian approach is used to solve the three-dimensional governing fluid equations (Navier-Stokes) around a self-propelling batoid. In this study, the swimming motions mimicking that of a manta ray (oscillatory mode) and of a stingray (undulatory mode) are used to investigate the salient differences in the thrust production mechanism between modes of swimming. The motion of the batoid is prescribed using a kinematic model fitted to actual biological data. The role of the key kinematic parameters (frequency, amplitude, and wavelength) and fluid parameters (Reynolds number) in the thrust producing mechanism is investigated. The vortex core structures of the wake are plotted and a correlation between the hydrodynamic signature of the different swimming modes and propulsive performance is established.