Flexible Micro Air Vehicle Wing Aerodynamic And Wind Characteristics Of Study

This dissertation developed two programs which suits for the computation of Micro flexible wings' aerodynamic characteristics. Based on these programs, the aerodynamic characteristics of two dimensional and three dimensional Micro flexible wings are investigated. Further more, the influence of structure deformation is also considered, the conclusions of this paper will supply qualitative instructions to MAVs' design.The XFOIL program is applied to compute the aerodynamic forces of Low Reynolds Number airfoils, the influence of fixed transition and turbulence are also investigated. The aerodynamic performances of active-deforming airfoils in horizontal and vertical gust are computed with modified XFOIL program, which are compared with the similar rigid ones'. The results show that the active-deforming airfoils yield better overall performances in gust.In this paper, some modules including unsteady computation, preconditioning matrix are added to the original Navier-Stokes program. The aerodynamic performances of wings with varied aspect-ratios and cambers are investigated on the basis of the program.To study three dimensional interaction between a flexible wing and its surrounding fluid flow, the computational fluid dynamics (CFD) and computational structure dynamics (CSD) are coupled. The forces acted on the wing are obtained through a preconditioned Navier-Stokes solver and the deformation of the wing is got through an universal finite element solver-ANSYS. The influence of aspect-ratio and Reynolds Number are also considered. The computational results indicate that the aerodynamic performances of flexible wings are better than the rigid ones' when the angles of attack exceed some value.