Why is the leading edge of a rear wing curved up?

Here are our CFD links and discussions about aerodynamics, suspension, driver safety and tyres. Please stick to F1 on this forum.
User avatar
Steven
Owner
Joined: 19 Aug 2002, 18:32
Location: Belgium

Why is the leading edge of a rear wing curved up?

Post

I've been wondering how this feature actually helps efficiency of a wing.
For example an image taken at Monza, the Ferrari rear wing sporting the upward leading edge, while MVR's wing is more straightforward.

Image

Anybody who can explain this feature?

Just_a_fan
Just_a_fan
593
Joined: 31 Jan 2010, 20:37

Re: Why is the leading edge of a rear wing curved up?

Post

At a guess, I'd say it's to help clean up the flow from the DRS activator. By shortening the chord locally you will alter the way the flow leaves the trailing edge. Probably helps to reduce turbulence from the DRS activator and thus improve overall efficiency.

Erm, ignore all of that. I was thinking about the v in the trailing edge. D'oh! :oops:
Last edited by Just_a_fan on 04 Oct 2011, 19:27, edited 1 time in total.
If you are more fortunate than others, build a larger table not a taller fence.

User avatar
raymondu999
54
Joined: 04 Feb 2010, 07:31

Re: Why is the leading edge of a rear wing curved up?

Post

But this feature was already on the MP4-25 I believe; was it not?
失败者找理由,成功者找方法

User avatar
flynfrog
Moderator
Joined: 23 Mar 2006, 22:31

Re: Why is the leading edge of a rear wing curved up?

Post

its a typical low drag setup. Take a look and the indy 500 wings.

Image

PNSD
PNSD
3
Joined: 03 Apr 2006, 18:10

Re: Why is the leading edge of a rear wing curved up?

Post

High nose up wings are typical for LMP racers at Le mans too.

proutyc
proutyc
0
Joined: 08 Jun 2010, 05:19

Re: Why is the leading edge of a rear wing curved up?

Post

Cant explain why it done but we have data from our like sports car 9similiar to radicals etc) we see an increase in straight line speed and G number up when using a small nose up. So far only 2 degrees played with.

Just know its works for us, I thought it must have something to do with staying attached to underside of the wing better

User avatar
horse
6
Joined: 23 Oct 2009, 17:53
Location: Bilbao, ES

Re: Why is the leading edge of a rear wing curved up?

Post

I would say that the angle of attack of the Ferrari wing is still negative (ie normal) or neutral and it just has a much higher camber than the Virgin wing.

That Virgin wing can't be making much DF at all, in comparison.
"Words are for meaning: when you've got the meaning, you can forget the words." - Chuang Tzu

User avatar
ringo
230
Joined: 29 Mar 2009, 10:57

Re: Why is the leading edge of a rear wing curved up?

Post

The bottom of the wing is like a half venturi.
The throat of the venturi, where there is the lowest pressure, would be in the middle of the wing for a curved lipped wing.

The curve make sense but it's difficult to fully expound on it.

It is more to control the pressure zones around the wing. These wings are generated from the characteristics, which is the reverse method from the clasical way of wing design.
Ussualy you make a wing then test it. You then get the characteristics, such as pitching moment Cl, Cd and where it is produced.

Nowdays, you decide what Cl and Cd you want and where you want it along the wing, and the airfoil is generated.

The curved leading edge is simply a result of the desired characteristics.


I was wondering this myself, especially with F1 wings having the belly in them.

edit:

to add to the venturi explanation, the air keeps accelerating towards the middle of the wing, where the hump is, so the speed increases and pressure drops. For a non curved front the air doesn't accelerate for as much.
For Sure!!

User avatar
Jeffsvilleusa
0
Joined: 15 Apr 2011, 00:14
Location: San Francisco

Re: Why is the leading edge of a rear wing curved up?

Post

If you imagine it as an upside-down airplane wing, it doesn't seem counter-intuitive (at least to me), or at least less so. To [needlessly?] elaborate, if an airplane wing's leading edge was dipped down a little (instead of up in the F1's case) it wouldn't look absurd because isn't it meant to divide the airflow by two differing paths? And the top of a plane wing is the convex part.

You might be surprised, but I'm actually not an aerodynamacist, but does this make sense?
Box! Box!

shelly
shelly
136
Joined: 05 May 2009, 12:18

Re: Why is the leading edge of a rear wing curved up?

Post

ringo, the lowest pressure line is near the leading edge even for a cambered wing. Forget Venturi.
twitter: @armchair_aero

marekk
marekk
2
Joined: 12 Feb 2011, 00:29

Re: Why is the leading edge of a rear wing curved up?

Post

It's just liebeck's airfoil (highly cambered profile designed for maximum lift).
Not used in aircrafts due to high drag coeff, but very common in race cars.
produces fair amount of downforce even at 0 AoA.

PNSD
PNSD
3
Joined: 03 Apr 2006, 18:10

Re: Why is the leading edge of a rear wing curved up?

Post

shelly wrote:ringo, the lowest pressure line is near the leading edge even for a cambered wing. Forget Venturi.
Yup.

Ringo, the method you state is not incorrect, I believe it's known as inverse design? Developed initially whilst looking at transonic aerofoils. However turbine, and compressor blades have probably found the best use of such methods.

Leading edge droop on A/C reduces the peak suction magnitude, and in doing so reduces what would be a large adverse pressure gradient.

User avatar
Steven
Owner
Joined: 19 Aug 2002, 18:32
Location: Belgium

Re: Why is the leading edge of a rear wing curved up?

Post

Some CFD simulation would be very useful here...

Seeing Ferrari's rear wing though, would it be unthinkable to have flow detaching above the lower plane, just behind the leading edge of the wing?

shelly
shelly
136
Joined: 05 May 2009, 12:18

Re: Why is the leading edge of a rear wing curved up?

Post

@tomba: I think flow detachment on top of mainplane in design condition (DRS closed) is quite unthinkable; it is less unlikely with DRS open - off design condition
twitter: @armchair_aero

User avatar
Steven
Owner
Joined: 19 Aug 2002, 18:32
Location: Belgium

Re: Why is the leading edge of a rear wing curved up?

Post

I thought so, but perhaps it's even interesting to have flow seperation there, reducing the amount of generated downforce and drag at higher speeds. Just guessing though...