Front Wing F-Duct

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Metalrulz
-1
Joined: 10 Oct 2011, 22:01

Re: Mercedes MGP W03

Post

But why test it on a higher nosecone car and let the cat out of the bag with the concept because the same technology could produce different results on next years lower nosecone car.

hardingfv32
32
Joined: 03 Apr 2011, 19:42

Re: Front Wing F-Duct

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1) What would you consider the primary functions of the front wing? Down-force and flow preparation for movement around the body?

2) Is this air flow through the small nose hole a signal/pilot circuit similar to the F-duct?

Brian

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raymondu999
54
Joined: 04 Feb 2010, 07:31

Re: Front Wing F-Duct

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Here's an image that was in that particular autosport magazine article:
Image
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n_anirudh
28
Joined: 25 Jul 2008, 02:43

Re: Front Wing F-Duct

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^^

Is that not the slot they already had?? as in the slot on the mainplane of the wing <before the FW fDuct was discovered >??

If this new F-duct slot is near the old slot, does the new slot blow normally or at an angle to disrupt the flow and stall a part of the wing??

gonek
0
Joined: 02 Sep 2009, 15:40
Location: Krakow, Poland

Re: Front Wing F-Duct

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IMO this all is a great bullsh*****. Auto Motor und Sport are very good friends of Daimler. They also come frome Stuttgart. They often help Daimler in marketing and another issues. Mercedes has made a deal with them. They publicate this pictrues and description of this "invention" in order to confuse another teams. They want that another teams waste time to investigate it!

volarchico
0
Joined: 26 Feb 2010, 07:27

Re: Front Wing F-Duct

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It'd be hard for anyone to know how long that slot has been there. We don't get very many good images of the underside of the wings.

hardingfv32
32
Joined: 03 Apr 2011, 19:42

Re: Front Wing F-Duct

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What is the primary goal of this system? Drag reduction, flow attachment??

Brian

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raymondu999
54
Joined: 04 Feb 2010, 07:31

Re: Front Wing F-Duct

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That's part of the speculation of this thread - some say... it's for drag reduction. Some say... it's for feeding the diffuser...

All we know is...

It's the front wing F-duct!
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Ian P.
2
Joined: 08 Sep 2006, 21:57

Re: Front Wing F-Duct

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This really sounds like a bunch of small brightly coloured oily fish.
What we can reasonably surmise form all of this...

- bleeding air over the top surface (or any surface) of a low incidence angle wing will NOT increase downforce
- it may stall the wing (slightly) and reduce drag and downforce
- the amount of air going through the duct is trivial to what is flowing around the car. This volume will NOT impact (directly) the splitter or difuser.
- there are no (legal) moving parts inside the duct, switching on or off will have to be done hydraulically
- the pressure on the nose opening and hence the flow through the duct will be related to speed squared, hence more flow at high speed, less at low.

If the system does something, it sure looks like it will reduce downforce and drag, more effect at higher speeds, less at low speeds. This would allow the front wing to be set up for more downforce knowing that it will be partially turned off at high speeds (lower drag).
If there is some form of hydraulic on/off feature inside the nose, it could work to respond to the turbulence (turn off the flow) when following another car and reduce the loss in downforce from the front wing.

Bottom line ..... gonek is probably right.
Personal motto... "Were it not for the bad.... I would have no luck at all."

hardingfv32
32
Joined: 03 Apr 2011, 19:42

Re: Front Wing F-Duct

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Is all the air flow conditioning for travel around the front wheels and to the rear of the car reduce that part of the front wing used to create down-force? Does this mean the those parts of the wing used for down-force must run at higher drag levels?

I am trying to develop a reason for this type of front wing design.

Brian

marekk
2
Joined: 12 Feb 2011, 00:29

Re: Front Wing F-Duct

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We should look as always at the whole car.
Even small amount of high pressure air on the sucking side of the wing can cause significant separation, and this disturbed, turbulent air travels downstream, influencing aero efficiency of all parts along the way (tea tray, floor's leading edge, diffuser ...), reducing total downforce and drag.

Outlet slits positioned at this part of the wing don't have (almost) any influence on outer sectors of the wing, so there is very little lost of FW's downforce and flow's conditioning function.

Should be relatively easy to tune by variating the diameter of used ducting, without changing the wing (slits) geometry.

hardingfv32
32
Joined: 03 Apr 2011, 19:42

Re: Front Wing F-Duct

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"high pressure air"

Why would this air be high pressure relative to where it is being released on the wing? What kind of pressure/flow are you going to maintain traveling through two 90 deg bends and the narrow wing struts? The F-duct was almost a straight shoot to the wing slot.

Brian

marekk
2
Joined: 12 Feb 2011, 00:29

Re: Front Wing F-Duct

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hardingfv32 wrote:"high pressure air"

Why would this air be high pressure relative to where it is being released on the wing? What kind of pressure/flow are you going to maintain traveling through two 90 deg bends and the narrow wing struts? The F-duct was almost a straight shoot to the wing slot.

Brian
Boundary layer on the sucking side of the wing has the same static pressure as surrounding flow - lower then ambient. In contrast, on the nose tip there is some compression of air molecules (not only on the lips, at those speeds one can expect up to 5% over ambient inside the nose just due to conversion of kinetic energy of air molecules entering through the opening). If you connect both openings, there will be pressure transfer even without any flow, no matter how many bends are inbetween (system of connected vessels).

And again, you need very little to trigger separation - Ferrari used at some point just a strip of zig-zaged tape for this (often used for the same purpose in sailplanes).

Per
Per
35
Joined: 07 Mar 2009, 18:20
Location: Delft, the Netherlands

Re: Front Wing F-Duct

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These zig-zagged tapes you are referring to cause the boundary layer to become turbulent which postpones flow separation (the same reason why dimpled golf balls have lower drag than perfectly round ones).

Could it be possible to let the air leave the slots at a greater velocity than the surrounding flow? And thus lower the pressure at the bottom of the wing and create more downforce? I think there's no way you can get some proper flow through such narrow ducts, but who knows... If it is possible, this would increase downforce but also drag (like sending air through a duct usually does).

Also, maybe the duct chokes above a certain velocity which would mean the drag penalty disappears (which explains the use of the term 'F duct').

Well, I don't know. I never liked aerodynamics so I'm not so good at it I guess. But it's a really interesting design - if it is a serious story.

LotusF1
0
Joined: 01 Oct 2009, 10:08

Re: Front Wing F-Duct

Post

Ian P. wrote:This really sounds like a bunch of small brightly coloured oily fish.
What we can reasonably surmise form all of this...

- bleeding air over the top surface (or any surface) of a low incidence angle wing will NOT increase downforce
- it may stall the wing (slightly) and reduce drag and downforce
- the amount of air going through the duct is trivial to what is flowing around the car. This volume will NOT impact (directly) the splitter or difuser.
- there are no (legal) moving parts inside the duct, switching on or off will have to be done hydraulically
- the pressure on the nose opening and hence the flow through the duct will be related to speed squared, hence more flow at high speed, less at low.

If the system does something, it sure looks like it will reduce downforce and drag, more effect at higher speeds, less at low speeds. This would allow the front wing to be set up for more downforce knowing that it will be partially turned off at high speeds (lower drag).
If there is some form of hydraulic on/off feature inside the nose, it could work to respond to the turbulence (turn off the flow) when following another car and reduce the loss in downforce from the front wing.

Bottom line ..... gonek is probably right.
if you blow air on top it will increase downforce, as long as it slows down then you will have positive pressure on top. the more massflow the more downforce.

as for the rest i cant say, need clear pictures. for me its all rubbish but who knows...and why on earth would they do it now when they have all winter test sessions to do it in secret. bah...