Study on influence of brackets on the aerodynamic performance of high lift system

By numerical simulation, the influence of slat tracks and flap track fairings on aerodynamic performance of highlift system and its flow mechanism have been investigated. The results indicate that these brackets just bring a little descent to the linear part of lift curve, but cause a remarkable loss to the angle of stall and maximum lift coefficient. The mechanism lies in that lowmomentum strong wake flow generated by slat tracks mixed with the boundary layer of main wing, which causes the remarkable loss of the lift. At high angle of attack, slat tracks will generate large area flow separation. The flap slot section area diminishes for blockage effect of flap track fairings. This made the high speed flow of flap slot faster, and made for blowing the separation flow on flap surface away.