11. This vortex acts like an aerodynamic fence and retards the flow separation region from encroaching into the tip region. 12. The felt delays flow separation in the boundary layer which reduces aerodynamic drag and gives the ball better flight properties. 13. Clean air under the car prevents flow separation from occurring in the diffuser, which would severely rob its performance. 14. As a result, there is flow separation , creating recirculating separation zones at the entrance of the narrower pipe. 15. Stages losses in compressor are mainly due to blade friction, flow separation , unsteady flow and vane-blade spacing. 16. A large flow gradient can lead to these factors, so flow separation and stagnation should be as small as possible. 17. :As particles flow along the channel the cross flow separation field pushes the molecules towards the bottom of the channel. 18. Contrary to the illustration, the aileron leading edge has to be rounded to prevent flow separation and flutter at negative deflections. 19. However, if the exit pressure is less than approximately 40 % that of ambient, then " flow separation " occurs. 20. Such flow separation causes a large increase in the pressure drag, since it greatly increases the effective size of the wing section.
