Analysis of Aerodynamic Failure and Prevention of Wings Under Vertical Gusts

Vertical gusts are often more destructive to UAVs than horizontal gusts, and short-term vertical gusts can cause drastic changes in the aerodynamic load on the wings. This study established the aerodynamic response model of the flat airfoil and NACA4412 airfoil under the action of vertical gusts based on the speed splitting method (SVM), taking the diffusion source term into account. The numerical simulation results show that the flow field structure and surface pressure distribution coefficient of NACA4412 airfoils undergo significant changes in a short time under the action of vertical gusts. In order to avoid aerodynamic failure caused by vertical gusts, active jet devices are installed near the leading edge of the wing to effectively alleviate aerodynamic separation caused by vertical winds with a gust ratio below 0.4. However, for large gust ratios above vertical winds of 0.6, the relief effect of the active jet device is not ideal, and the aircraft should be controlled flexibly to reduce greater losses. This research can provide technical reference for route planning and aerodynamic control of long-range UAVs.