Reconfiguration of a Highly-Flexible Plate Impacting a Free Surface *

Passive reconfiguration of flexible structures readily occurs in biological structures through fluids such as air and water. This phenomenon has been studied in detail to understand how structures such as seagrass and leaves conform to more streamline deformed structures under drag force in flow media. In this talk, the reconfiguration of highly flexible plates during water impact is experimentally investigated. The model is a V-shape wedge, which is made of two highly flexible cantilevered plates connected by a rigid bar at the apex. As the wedge falls into the water, the deformation of the flexible bottom plates due to impact is captured using high-speed photography. The displacement and acceleration of the model is recorded using a potentiometer and accelerometer, respectively. Particle Image Velocimetry (PIV) will be utilized to quantitatively evaluate the fluid velocity and pressure surrounding the plate. Simultaneous measurements are then analyzed to study the correlation between passive reconfiguration and hydrodynamic loading exerted to the plates. The experimental measurements and results presented in this talk will shed light on drag reduction techniques on highly-flexible plates near a free surface.