Fluid-structure interaction of a flapping flexible plate in quiescent fluid

► Fluid-structure analysis combined with FEM and LBM is presented to study a flapping flexible plate in a quiescent fluid. ► The proposed fluid-structure analysis scheme is rigorously validated with classical examples. ► The propulsion efficiency is improved by the flexibility of the flapping plate. ► The optimized elasticity of the flapping plate for efficient propulsion exists.