Propulsive performance of two- and three-dimensional flapping flexible plates

The propulsive performance of two- and three-dimensional (2D and 3D) flapping flexible plates in a fluid at rest is investigated by a finite element method for the plate motion and an immersed boundary-lattice Boltzmann method for the fluid flow. We consider a model that as the leading-edge of the plate takes a vertical oscillation, the entire plate moves freely due to the fluid-structure interaction. The effects of flexibility on the dynamics of the 2D and 3D flapping plates are investigated. It is found that a suitable flexibility is benefit for improving the propulsive performance. The results obtained in this study provide physical insight into the understanding of the dynamics of the flapping-based locomotion. (C) 2015 The Authors. Published by Elsevier Ltd on behalf of The Chinese Society of Theoretical and Applied Mechanics.