A Numerical Study Of Fluid Mechanics Of Flapping Wings

The understanding of the unsteady fluid mechanism during wing flapping is important in the design of robotic fish and micro-aerial vehicles. In recent years, a lot of research has been done on flapping wing. However, as the unsteady flow of flapping wing is rather complex, many detals of its fluid field is still unknown.In this paper, we simulate flapping wings in heaving motion by numerical method using OpenFOAM, which is open source CFD software. To investigate the thrust generation of heaving wings, horizontal force is devided into viscous force and pressure difference force. We analysize the effects of Reynolds number, heaving amplitude, thickness, shape and three-demensional conditions. The results show that the fluid field in unsteady flow is very different from that of steady condition and the fluid dynamics is closely associated with the vortex structures. In addition, viscous force can produce thrust in particular condition.