Front Wing F-Duct Idea

I recently saw this idea for a front wing F-Duct:

http://videos.caranddriverthef1.com/video/d0a182df002s.html

Not a bad idea, but it definitely has its flaws.

1. A major issue would be having the F-Duct in operation in all straight line situations, such as braking, when you clearly want lots of downforce.  This would limit braking ability.

2. You’d want downforce on both sides of the wing during cornering – it’s better to have more downforce on both sides, rather than less downforce overall albeit specifically focused on the inside.  Personally, I can’t see how trying to get more downforce solely on the inside would be much of a benefit; he could have had the idea that flattening the car to make the underbody work better, but I think that front wing is too flexible for it to work.  It’s mounted in such a way that any torque applied by having one side of the wing work harder than the other wouldn’t exactly transfer to the chassis, from what I can see, and would likely just twist the wing awkwardly.

3. How would you get it to transition between blowing the elements at a specific yaw to separating the airflow in a straight line?  What if the car were to slide just a little?  Suddenly the air goes from the outside passage (creating downforce) to the middle (reducing drag and downforce), thus causing the car to want to understeer… but once it understeers, the airflow goes back to the outside passage.  This could cause some instability…  Then, if the car were to twitch a little harder, it would go from the outside passage to the middle to the inside passage; in that time, the driver could be reacting to the aero balance when the car has less front downforce, and suddenly the front gets a lot more when it transitions to inside passage, creating a major shift in balance.  These rapid shifts in balance could make the car very difficult to drive, similar to the porpoising that Ayrton Senna experienced in early 1994 because his Williams’ front wing was too low.

4. The two functions (blowing for more downforce and separating for less drag) would likely require different amounts of air, and probably couldn’t use the same inlet.  For blowing, you need a lot of volumetric flow at a high velocity, which is something that that system would have a hard time with, considering all of the small inlet, small tubing, high number of bends and other restrictions the air would experience.  At best, you’d get a system that would barely offset the penalty induced by having a slot/disruption across the underside of the wing.  The drag reduction idea is plausible, but the blowing idea doesn’t seem to be.

5. He also has the slots in the wrong positions; you’d want to separate the flow on the main element of the wing, not the last flap… trip the flow earlier and you reduce that much more drag… in addition, you would want to blow the wing more toward the rear to add energy to the boundary layer – basically creating a jet that will help suck up the air toward the back of the wing to keep it attached.

I just can’t see how that would be a smooth transition, since by definition and design, it’s a logic system using fluid flow, so it’s either on or off.  With the old F-Ducts on the rear, it was driver-controlled (or speed-controlled in Mercedes’ case), so it would be up to the driver (or tuned to a specific speed) to engage, and not potentially engage mid-corner.

I think the best bet for this concept would be to use a Mercedes-style speed-controlled F-Duct for the straights only.  If I understand their system from 2010 correctly, it would engage only at speeds higher than the fastest corner that requires full downforce.  The same thing could be done to the front wing, ensuring that if the fastest corner is 215 km/h, then it would engage at 220, so every straight above that speed would get a drag reduction.  That way, in the corners, the yaw wouldn’t lead to rapid engagement and disengagement resulting in massive instability due to rapid shifts in aerodynamic balance.

Unfortunately, blowing the wing passively, using a ram-air intake, doesn’t seem feasible.  To get the airflow and the jet needed to measurably increase downforce, you would need a big scoop that would cause more drag than what it’s worth.  Personally, I’d like to see if he did more CFD than just the basic function of the fluidic switch, and see if he was able to come up with some downforce and drag figures.

Smart idea, but I don’t think his all-compassing solution would actually be feasible.

Edit: I might be wrong!  According to this site, Mercedes might be using this idea.

http://www.f1racingmotor.com/mercedes-wing-innovation-called-w-duct/

I still think they’d have to figure out how to have a smooth transition, and it might also have a speed-related engagement… and they’d have to figure out how to get a high-velocity flow from a small intake… and they’d have ensure that if the car began to slide, the aero-balance of the car wouldn’t have sudden changes.  Tricky!  …then again, if anyone can do it, it’d be an F1 team that’d have the ability.

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