Snail feeding: Thin film flow with an undulating surface

Apple snails (Pomacea canaliculata) collect food particles on the free surface by deforming their feet and generating periodic undulations underneath the air-water interface. Inspired by this peculiar feeding behavior, we develop a 2D thin-film mathematical model to explore the physical mechanism of free surface flows driven by periodic undulations. We find the surface undulations cause normal stresses that deform the air-fluid interface and drive a net flow, which is directly controlled by the fluid properties and the undulation wave speed. Our model also demonstrates the effects of inertia that can significantly alter thin-film flows, in good agreement with the experimental observations. In this talk, we will discuss some preliminary model results along with the experimental findings and offer plausible physical mechanisms driving the flow system.