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Explaination of front wing design

Morning all, Can someone explain the reason for these 'notches' in this wing's gurney flap please? are they vortex generators?

http://i45.tinypic.com/in5zzq.jpg

They sure look like it.

Serrated edges are becoming a trend in aviation to reduce drag on sharp edges (see Boeing 787 engine nacelles), but in more crude ways, were also used to quieten old 707 engines (which received flower-shaped hush kits that better / quieter mix the air going through the engine, with the air that's been going around the engine nacelle.

http://3.bp.blogspot.com/_uRX1wGVlxM...0/hush+kit.jpg
or
http://www.airliners.net/photos/small/1/9/4/0313491.jpg

Thanks for reply - so what purpose do these serve only being in the centre?

To reduce buffeting on the GoPro? I don't know. Did you get a chance to talk to the team members? I'd ask them what wind tunnel facility they use.

Quote:

Originally Posted by Tango Charlie (Post 309910)

To reduce buffeting on the GoPro? I don't know. Did you get a chance to talk to the team members? I'd ask them what wind tunnel facility they use.

GoPro?

The video camera mounted on the top, a couple feet behind the front wheels.

Quote:

Originally Posted by Tango Charlie (Post 309914)

The video camera mounted on the top, a couple feet behind the front wheels.

Got you, nah that's the fuel tank vent, has a cover on that is removed before a run.

Brilliant perspective of the photo may provide a clue to the answer. The car body is beyond, and I suspect the ridges break up a standing wave caused by the down-force vortex which forms following a Gurney Flap.

F1JOURNAL.COM
http://www.f1journal.com/photos/gurney_004.jpg

My experience on this topic is in acoustics (4-years ago):
Do you have a variable splitter plate? - The Virtual Hoverrally - Page 2

Quote:

[quote name='kach22i' timestamp='1280573265' post='21585']
Don, you are correct, everything each side of the fan is a noise source. The closer in proximity the object (splitter, support mount...etc), the more noise potential. I have successfully lowered the perceived noise of my Scat II by distributing the sound nodes (energy pattern) of the splitter plate.

My splitter plate's leading edge is now wavy (serrated) with an undulating edge, not unlike that of a bread knife. The concept here is that perceived loudness is based on the highest sound node (peak) and typically higher frequencies are also thought of as louder over similar lower tones. I also moved the splitter closer to the fan so it should be a wash between pressure escaping though the uneven edge verses a straight edge further back.

5 Ways to Use a Serrated Knife... Other Than Cutting Bread! | The Kitchn
http://www.apartmenttherapy.com/uima...ratedKnife.jpg

Pictures by kach22i - Photobucket
http://i184.photobucket.com/albums/x...22i/HOV102.jpg
http://i184.photobucket.com/albums/x...22i/HOV104.jpg
http://i184.photobucket.com/albums/x...22i/Wave-1.jpg

Making a tail cone - foam - The Virtual Hoverrally - Page 2
http://i184.photobucket.com/albums/x...22i/DUCT-1.jpg
Even at idle it's effects are very noticeable. Notice too that the lip points into the flow at right angles depending which side of the thrust swirl you are on

[/QUOTE]

Quote:

Originally Posted by Bennett_Racing (Post 309889)

Thanks for reply - so what purpose do these serve only being in the centre?

I'd go with TC :
- reduce buffeting on the car's fuselage, or on the driver's helmet

- if it works as far back as the driver's helmet, those 3 circles above the seat are likely intakes ? Then it could help there as well .

- maybe even out pressure over the vent hole, rather than have a pulsating effect ?

Have you ever driven a motorcycle with an ill-adjusted or ill-conceived screen ?
The buffeting is debilitating.
One way to solve this buffeting is dimples - which are VG in the gliders' world ;) - near the top of the screen.

My guess is that without the whale fin tubercules,or raptor feathertips,that there is something about the frequency and amplitude of the shedding vortices approaching the dragsters body that the crew didn't like,so they've altered them with this mod.Which goes with the 'accoustics' comment mentioned by Kachi above.