Meeting Abstract
Suction feeders generate a flow of water that draws the prey into the mouth. This process involves extremely unsteady flow, outside as well as inside of the mouth cavity. Especially for flow patterns inside the mouth cavity and related dynamics and energetics (e.g. the forces, muscle work, and power requirements) for expanding the mouth cavity, our current knowledge is largely based on modelling studies. Computational fluid dynamics (CFD) is a mathematical modelling technique that allows a more complete and accurate assessment of suction feeding hydrodynamics compared to previous modeling approaches. It simulates fluid flows by numerically solving the motion equations for a fluid volume divided into a mesh containing a large number of small volume elements. Using CFD software that allows the surface mesh of the head of the animal to be programmed to deform as observed in vivo, the three-dimensional flow patterns as well as the instantaneous hydrodynamic forces exerted at the surface of the head can be calculated, hence enabling inverse dynamic analyses. In this presentation, examples of new technical advances and biomechanical insights based on dynamic-mesh CFD models will be given. This will include how Chinese giant salamanders generate suction by separating their long and wide jaws, how the quickly rotating and widening snout of seahorses is employed to capture prey, and how the outflow of water through the opercular slits in fish can be modelled.
