12.8: Display Free Vortices (wake turbulence)
Every wing has outgoing free vortices at the trailing edge. They are part of horseshoe
vortices and continue in the infinite.
To avoid chaotic lines in the 3D-graphic, only a part of the wake turbulence is
displayed. The length of wake turbulence is adjustable; this issue is covered
by chapter 'Design Computation'.
The marked button is in charge to make the wake
turbulence visible / invisible.
The following picture shows a wing with flap in left segment. You can see plain
wake turbulence, as used in most Vortex-Lattice programs. The visible part of
wake turbulence is limited to 1 meter.
If one calculates the design with iteration for wake turbulence, one can see
not only tip vortices, but also vortices at the flap edges. These vortices are
the reason for less lift at wing tips and for induced drag.
The following pictures illustrate where to take vortices into account. Believe
it or not, even a ring wing produces a nice little wake turbulence.