Mercedes AMG F1 W05

[turbof1]

Steven got around posting my analysis of the mercedes front wing:
http://www.f1technical.net/features/19180

If I got anything wrong, please please let me know!

[markn93]

Fantastic piece, great work.

[Owen.C93]

Interesting how the little winglet points down but on the new McLaren end plate it curves upwards.

[Just_a_fan]

I think the little winglet on the endplate is there to do one thing - create a powerful vortex that will try to keep the flow around the front tyre "attached" in order to fill in the wake immediately behind the contact patch. This will help to reduce drag and also clean up the flow off the tyre so helping preserve the carefully conditioned flows going around the sidepods and barge boards.

[gray41]

W05 steering wheel.

[RicerDude]

Is that Hamiltons' wheel or are they the same for both drivers?

[Montyinct]

TBone thanks a lot!

[dans79]

what effect do you guys think the new front wing/nose will have on the car in Melbourne?

[Burgess]

what effect do you guys think the new front wing/nose will have on the car in Melbourne?

Less understeer.

[bhall]

Steven got around posting my analysis of the mercedes front wing:
http://www.f1technical.net/features/19180

If I got anything wrong, please please let me know!

More elements and longer slots keep the wing from stalling at high angles of attack. While technically they can use that for higher angles of attack, I believe it’s more a solution to the turbulent air from the rotating wheel, which normally messes up the airflow beneath the wing. Bleeding off cleaner airflow to underneath the wing will help in keeping airflow underneath the wing attached, preventing sudden downforce loss.

If only there was a way to utilize the turbulent air around the wheels...

In 2010, McLaren introduced the F-duct, a driver-activated system that demonstrated the benefit of "stalling" a wing to reduce drag. When activated, air flow from a jet aimed perpendicular to the boundary layer on the underside of the wing caused that boundary layer to detach. The subsequent loss of downforce resulted in reduced drag, because it effectively transformed the rear wing into a bluff body, which has far less wake. (At least, I think that's how it worked.)

Mercedes went a bit further and applied this concept to the front wing of the W03 in 2012. So, the use of a disruption of some sort to reduce drag via reduced downforce is pretty well established at this point.

It's my understanding that teams now try to use the disruptive nature of air churned around by the front wheels to reduce downforce, and thus drag, created by the front wing. This happens because downstream events have upstream effects. As such, when a car is driven straight ahead, the alignment of the front wheels inhibits the effectiveness of the outboard portions of the wing and endplates - areas where most downforce is created. This is ideal, however, because cars don't generally need downforce in order to be driven straight ahead.

(EDIT: For the record, I really regret the way I worded that. I think this is better.)

They do need downforce in order to turn, though.



To that end, when a driver steers for a corner, the outside wheel is largely removed from the downstream path of the outer wing and endplate. No longer thwarted by blockages, the sudden effectiveness of those devices quickly gives the car a significant jolt of downforce, which is enhanced further by any outward flow from the inner portions of the wing. Everything gets rolled up into a big, downforce-creating vortex that's shed from the top outside corner of the endplate and would otherwise be a massive pain in the ass if it was a constant feature of the car.



Incidentally, the black tabs on the outside of the endplates - likely from Aldo Costa, who used them on the F60, by the way - are probably designed to "shield" the vortex from oncoming flow, or perhaps to reduce pressure locally thereby encouraging the high-pressure air flow to vent behind them during the turn. But, those are just guesses.

The net result of all this is downforce when you need it for quick turn-in and reduced drag when you don't. The trick is getting it to work. With F1's ridiculously high yaw rates, many things have to happen in a very short period of time and in an environment often filled with genuinely random air flows. Moreover, cornering flow apparently can't be modeled in any wind tunnel; it only recently became possible to simulate in CFD. And I'm sure the new, narrowed wings haven't done aerodynamacists any favors, either.

You can see the pressure changes in the frames below. The car is in a simulated left turn. Note how the pressure drops on the right side of the front wing throughout the turn. That's right where you need it.

[YUL-F1]

The CFD pics are great and very informative but I can't help but wonder why they don't have the tyres pointing at the correct angle for the rate of turn being simulated given their goal of doing such an exercise. What about tyre deformation?

[Richard]

A quick reminder that the car threads are meant to focus on the actual features of the actual car.

Discussion of lap times & tyres belong in the respective race and test threads.

For the avoidance of doubt, these threads are for posts about things you can touch or see - ie what is it or how does it work.

[Emerson.F]

Great stuff thanks for the explanation. Very insightfull. =D>

[timbo]

The car is in a simulated left turn. Note how the pressure drops on the right side of the front wing throughout the turn. That's right where you need it.

http://i.imgur.com/CVCP7hH.png

I have problems with this statement. I'd rather help unloaded wheel (inside = left). Maybe I'm not getting something.

[turbof1]

Steven got around posting my analysis of the mercedes front wing:
http://www.f1technical.net/features/19180

If I got anything wrong, please please let me know!

More elements and longer slots keep the wing from stalling at high angles of attack. While technically they can use that for higher angles of attack, I believe it’s more a solution to the turbulent air from the rotating wheel, which normally messes up the airflow beneath the wing. Bleeding off cleaner airflow to underneath the wing will help in keeping airflow underneath the wing attached, preventing sudden downforce loss.

If only there was a way to utilize the turbulent air around the wheels...

In 2010, McLaren introduced the F-duct, a driver-activated system that demonstrated the benefit of "stalling" a wing to reduce drag. When activated, air flow from a jet aimed perpendicular to the boundary layer on the underside of the wing caused that boundary layer to detach. The subsequent loss of downforce resulted in reduced drag, because it effectively transformed the rear wing into a bluff body, which has far less wake. (At least, I think that's how it worked.)

Mercedes went a bit further and applied this concept to the front wing of the W03 in 2012. So, the use of a disruption of some sort to reduce drag via reduced downforce is pretty well established at this point.

It's my understanding that teams now try to use the disruptive nature of air churned around by the front wheels to reduce downforce, and thus drag, created by the front wing. This happens because downstream events have upstream effects. As such, when a car is driven straight ahead, the alignment of the front wheels inhibits the effectiveness of the outboard portions of the wing and endplates - areas where most downforce is created. This is ideal, however, because cars don't generally need downforce in order to be driven straight ahead.

They do need downforce in order to turn, though.

http://i.imgur.com/Jcb0BD0.jpg

To that end, when a driver steers for a corner, the outside wheel is largely removed from the downstream path of the outer wing and endplate. No longer thwarted by blockages, the sudden effectiveness of those devices quickly gives the car a significant jolt of downforce, which is enhanced further by any outward flow from the inner portions of the wing. Everything gets rolled up into a big, downforce-creating vortex that's shed from the top outside corner of the endplate and would otherwise be a massive pain in the ass if it was a constant feature of the car.

http://i.imgur.com/mlwnbs7.png

Incidentally, the black tabs on the outside of the endplates - likely from Aldo Costa, who used them on the F60, by the way - are probably designed to "shield" the vortex from oncoming flow, or perhaps to reduce pressure locally thereby encouraging the high-pressure air flow to vent behind them during the turn. But, those are just guesses.

The net result of all this is downforce when you need it for quick turn-in and reduced drag when you don't. The trick is getting it to work. With F1's ridiculously high yaw rates, many things have to happen in a very short period of time and in an environment often filled with genuinely random air flows. Moreover, cornering flow apparently can't be modeled in any wind tunnel; it only recently became possible to simulate in CFD. And I'm sure the new, narrowed wings haven't done aerodynamacists any favors, either.

You can see the pressure changes in the frames below. The car is in a simulated left turn. Note how the pressure drops on the right side of the front wing throughout the turn. That's right where you need it.

http://i.imgur.com/CVCP7hH.png

A very nice insight into this (clearly I must have raddled the cages for you with that post in the voting system topic )!

I have remark though about downstream effects on upstream elements: airflow reattachment. When entering the corner, you don't inmediately have the downforce back you shed by having the wheel wake disrupt the underflow of the wing. It takes a little bit of time before the downforce returns. That can result in unpredictable drive ability.

It's was also an issue with the aforementioned DDRS from mercedes: they blew the front wing, but because the air for had to make quite a long walk, it made life a bit more difficult right during corner entry. The f-duct in that aspect was different, as the driver could just lift his hand a split second before braking, reattaching the airflow in time.

That being said, it's believed red bull in the second half of last year found the means to reduce drag substantially. Since it's assumed they didn't use anything like DRD's, they must have found ways with the front wing-wheel wake interaction, and with vortices. That's a very complex matter though: you don't want to just encourage wheel wake, because it's responsible for a huge part of the car's drag. You could easily nullify the advantage, stalling the front wing through front wheel wake, by an increase in front wheel wake itself.