1. Airflight Vortex Guang-Xing Li

2. If you can not see the video, please insert the plug-in http://skp.mvps.org/downloads/YouT ubeVideo2k7.zip

3. Vortex Curl of Velocity Angular momentum carried by the flow

4. Observations Travel from Beijing to Hailaer, summer, 2010 Boeing 737, Cloudy day

6. Wing Structure

7. Zooming in--Launching

8. One Possible Explaination Vortex Due to Wing Shape

9. One Possible Explaination Vortex Due to Wing Shape

10. One Possible Explaination Vortex Due to Wing Shape

11. Fluid Motion Rotation Axes Aileron Wing Flap

12. Change of Pressure Pressure change due to vortex

13. Phase transition(water vapor condensation) due to Pressure deviation

14. Vapor Phase Transition

15. For 0.004 atm, we need relatively humidity of 0.985 (Reasonable)

16. Summary Wing configuration can generate vortex The pressure inside the vortex will drop, due to rotation Pressure difference induced by vortex rotation is enough to drive water condensation

17. Wing-Tip Vortex

19. Wing-tip Vortex

20. Vortex Evolution G. Huppertxs ppt

24. Vortex can be generated during the flight Sometimes visible, due to water vapor condensation Sometimes invisible, can be observed through dynamical effects – Dangerous for small aircrafts

26. Vortex Diffusion G. Huppertxs ppt

27. Summary Wing configuration can generate vortex The pressure inside the vortex will drop, due to rotation Pressure difference induced by vortex rotation is enough to drive water condensation Other ways to generate vortex during air flight?

28. How they fade: diffusion? Diffusion equation. Difficulties: – Re ~ 10^3, Turbulent Diffusion – Vortex-Turbulence Interaction, Vortex-Vortex inter. Lasts for a few minutes Complicated Interaction in later stages