I have tried reading the notes on the wing tip, but didn't understand well. How will the vortex be reduced on the wing tip.
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2$\begingroup$ Hi Abdulshakur, welcome to Aviation SE! Please explain in more detail what you have understood so far. It will be much easier to answer if you tell us where you got stuck. Did you look already at this answer? $\endgroup$– Peter KämpfMay 2, 2018 at 10:12
2 Answers
Wing vortices cannot be reduced. It is a byproduct of creating lift. The various wingtip shapes help to combine the airflow from the top and bottom of the wing and can make the wing act like it is longer and creating the same lift, but the vortex is still generated. The biggest vortices are created by the big airplanes when they are heavy, dirty (lots of flaps, etc. deployed) and slow (i.e. takeoff and landing). Even my little 4-seat Cessna Cardinal creates vortices.
See Section 3.14 here http://www.av8n.com/how/htm/airfoils.html#sec-vortices of this great e-book "See How It Flies" http://www.av8n.com/how/
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$\begingroup$ Technically speed does not matter, angle of attack does. Higher AoA results in stronger wingtip vortices. $\endgroup$– SamiMay 2, 2018 at 13:10
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$\begingroup$ As a small plane pilot, I typically only encounter the larger planes near the ground when they are going slower. They can climb to altitudes well above me very quickly with their jet engines, so slow and dirty is where I am most concerned about being upset by their vortices. I took off after a Gulfstream (G5 I think) on Saturday, had to wait 2-3 minutes after it departed before I was cleared for takeoff. $\endgroup$ May 2, 2018 at 13:17
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$\begingroup$ Yes, because when flying slow, planes generally have higher AoA. But they aren't the same thing. That's why I pointed it out. That is also why the vortices stop when the plane lands, AoA is 0, no vortices though the plane is still moving (slowly). $\endgroup$– SamiMay 2, 2018 at 13:38
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1$\begingroup$ Wake turbulence is greatest when an aircraft is heavy, clean and slow. See this FAA paper $\endgroup$– PondlifeMay 2, 2018 at 13:43
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$\begingroup$ Huh, I would have thought dirty with flaps, slots, slats all hanging out for extra lift. I guess not tho: " The greatest vortex strength occurs when the generating aircraft is heavy-slow-clean since the turbulence from a “dirty” aircraft configuration hastens wake decay. " That AC is waaay better than what was available when I got my license & Instrument rating many years ago. $\endgroup$ May 2, 2018 at 15:49
Vortices are shed along the entire span of the wing and are proportional to the lift produced. To reduce the strength of the vortex at any single point along the wing, including the wingtip, you can increase the span. This does not change the required lift or the total amount of energy going into the sheet.