Vortex Generators

[alberto1980 0]

Hi,
has anyone ever tried to put vortex generators on a wing suit?
If yes, what was to performance gain, if measured?

[kallend 1,646]

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Hi,
has anyone ever tried to put vortex generators on a wing suit?
If yes, what was to performance gain, if measured?

What would be the purpose?

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The only sure way to survive a canopy collision is not to have one.

[RMK 3]

Probably not a bad idea to experiment with. They do this to airplane wings http://www.avweb.com/news/reviews/182564-1.html

Though few wingsuit arm wings are as aerodynamically clean as planes

"Pain is the best instructor, but no one wants to attend his classes"

[alberto1980 0]

The purposes are many:
decrease drag in areas of flow separation, increase the maximum lift coefficient, improve handling characteristics during maneuvers. I am not a wing suit flyer but I have experience with VGs on aircrafts wings and I think they have some potential on wingsuits as well. If somebody wants to try I could give support, it would be very interesting.

[LouDiamond 1]

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Hi,
has anyone ever tried to put vortex generators on a wing suit?
If yes, what was to performance gain, if measured?

Do you mean something like THIS or THIS?

"It's just skydiving..additional drama is not required"
Some people dream about flying, I live my dream
SKYMONKEY PUBLISHING

[alberto1980 0]

I think those are just the scoops to inflate the wing.
I am talking about VGs on the fabric close to the leading edge (in this case the arm of the guy/girl). basically they are little wings at an incidence to the LOCAL flow angle that, due to their low aspect ratio, produce a vortex that mixes high momentum air at a distance from the suit towards low momentum air closer to the suit, thus creating beneficial effects. Hey I am not telling they work on a wingsuit, I said they might, since they do on rigid wings. It would be cool to see.
BTW, you can also sometimes find them at the rear ends or upstream of gaps on large trucks. they use them to reduce drag, since it pays off for them in terms of fuel.
About the installation on a wingsuit, I guess they could be glued on the fabric in the correspondence of the ribs. they could be made of fairly rigid rubber. just speculating..

[alberto1980 0]

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...few wingsuit arm wings are as aerodynamically clean as planes

That's why they may be beneficial. If a wing is superclean and well designed, no need for VGs

[kallend 1,646]

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...few wingsuit arm wings are as aerodynamically clean as planes

That's why they may be beneficial. If a wing is superclean and well designed, no need for VGs

Ummm... no. I don't think you understand what VGs do.

...

The only sure way to survive a canopy collision is not to have one.

[LouDiamond 1]

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I think those are just the scoops to inflate the wing.

No, those are not how the wing is inflated, that inlet is on the underside of the suit(think arm pit). What I posted is the closest thing you will find to what you are talking about. While they do work,based on wind tunnel testing done on a wingsuit, they are no longer used. Shape was crucial to their performance and lack thereof negated any benefit. Since then, all manufacturers have done away with their use.

"It's just skydiving..additional drama is not required"
Some people dream about flying, I live my dream
SKYMONKEY PUBLISHING

[alberto1980 0]

Ok, so they did try already. So basically they were beneficial from wind tunnel tests but too sensitive to position/dimension, therefore not used anymore?

[alberto1980 0]

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...few wingsuit arm wings are as aerodynamically clean as planes

That's why they may be beneficial. If a wing is superclean and well designed, no need for VGs

Ummm... no. I don't think you understand what VGs do.

Can you explain then?

[pchapman 262]

This probably wouldn't be the right application for traditional vortex generators, although possibly for another kind.

Traditional vortex generators are used slightly ahead of where attached flow would separate, adding energy that keeps the airflow attached to the surface for a longer distance and thus preventing a stalled region with little lift.

I'm not sure that the attached flow on a wingsuit goes very far back from the leading edge, and a bunch of small vortex generators probably isn't going to make a difference given the angle of attack and quality of the wing. I'd guess one is dealing with one big separated flow vortex over each wing, as is typical for a low aspect ratio swept delta wing or similar at high angle of attack. Much lift then comes from the low pressure within the vortex.

But I don't know much about airflow studies on wingsuits and haven't been watching the arguments in the last couple years.

That doesn't rule out that one could have fewer, larger vanes or slots or something that set up a few larger lift producing vortexes. But it sounds fiddly structurally and could interfere with the main vortex too.

So who knows.

[kallend 1,646]

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...few wingsuit arm wings are as aerodynamically clean as planes

That's why they may be beneficial. If a wing is superclean and well designed, no need for VGs

Ummm... no. I don't think you understand what VGs do.

Can you explain then?

Clean wings are MORE susceptible to flow separation. That's why you see VGs on 737s, 767s, learjets, and the White Knight II, all of which have very clean wings.

...

The only sure way to survive a canopy collision is not to have one.

[alberto1980 0]

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Clean wings are MORE susceptible to flow separation. That's why you see VGs on 737s, 767s, learjets, and the White Knight II, all of which have very clean wings.

Everything you mention is transonic aircrafts. There VGs serve the purpose to reposition shock waves, but this is another story, I don't want to get into nerdy aerodynamic discussions here, just wondering about VGs and wingsuits, and LouDiamond gave me the answers. Thanks for the discussion guys.