Analysis of fluid and solid interaction of the flexible bionic wing in ground effect

Abstract

Animals can obtain excellent locomotion performance as they swim or fly under ground effect in nature. Inspired by this, fluid mechanisms of the flexible bionic wing oscillating and gliding in ground effect are investigated by fluid–solid interaction simulation in this study, respectively. For the oscillation motion, the flexible wing vertically moves up and down at different distances from the ground. Different parameters such as the average height from the ground, oscillation frequency of the flexible bionic wing, and airfoil flexibility are considered in the simulation. At the same time, the gliding motion of the flexible wing in the ground effect is also studied, compared with the oscillation motion. Several simulations are set for different parameters. The characteristics of the force and deformation of the flexible wing and the flow field around the flexible wing are analyzed in depth. The effects of different flexibilities on the force characteristics of oscillation and gliding motion are obtained. The results show that the influence of flexibility on the lift and drag force is different. Optimal motion performance can be achieved within a certain range of flexibility. The ground effect features of the flexible bionic wing with different locomotion modes are acquired.