Influence of Reciprocal Effect Between Swimming Models and Undulating Fin Morphology on Robotics Propulsion Performance

We have previously designed an undulating robotic fin, which is inspired by the pectoral fin of stingray. A CFD-based comparison of optimal thrust and efficiency generation was made among four typical fin undulating swimmingmodels with different amplitude envelopes as well as the fin morphologic. To complement these studies, we consider in this paper the influence of reciprocal effect between swimming models and morphologic on the fin propulsion performance by both CFD and experiments methods. An unstructured, grid-based, unsteady Navier-Stokes solver with automatic adaptive re-meshing is used to compute the unsteady flow around the fin through twenty complete cycles. The pressure distribution on fin surface is computed and integrated to find fin propulsion forces. We conclude from the simulation that the compliance of the distribution mode of fin outline with amplitude envelope can generate the best propulsion performance. An experiment was conducted to verify the simulation results. It is hoped that the work concluded is useful for the optimal design of undulating robotic fins.