Surface swimming using high-frequency, low-amplitude motions*

An experimental investigation is conducted to study the thrust generated by a flexible flat plate at the air-water interface. The flat plate is driven by a voice coil actuator, which heaves the leading edge at a prescribed frequency and amplitude. In particular, the kinematic regime of interest is high frequency (10-100 Hz) and low amplitude (4 mm or less). These motions generate surface waves in addition to bulk flow beneath the surface, which together produce thrust. The thrust and mean flow field will be measured by using a load cell and particle image velocimetry, respectively. High-speed imaging will be used to visualize wave patterns on the surface and bending dynamics of the flat plate. Results will contribute to understanding the role that flexibility and wave production can play in surface swimming.