2018 aero developments

[Vanja #66]

Right on the money. This is why this car was so fast. They knew and they've focused on this area over the winter.


Raked cars especially benefit from this as it's in line with the floor, it's the most ground effect wing on the car. Also, riddle me this, what are the deflection limits on that part of the floor? The possibilities are endless, but first step would be for McLaren to ditch that vertical plate, and add more chicken wing, and rely on vortex generators upstream to guide airflow instead of that plate.

That car was fast because they had a good concept and they dared to try new ideas. Also, they had the best aero package (or at least one of) in pre-2009 era and there are a lot of small, but important similarities that can be brought together and compared between these cars today and those cars from 10+ years ago. So they probably knew (or had a pretty good idea) what to do and what not to do to make a good use of barge board pieces.

The single most important thing for any car, aero wise, is that it works well together. So if one piece falters in reality, everything breaks apart. Ferrari had structural issues (probably too much vibration) that caused them to lower the rake in Australia, bringing up front wing and loosing them a good frontal aero and a good balance of the car. They needed new set up to solve this for Bahrain and new structure of the floor in China made them shine in Qualy. At the oppposite end, you have Williams, who have some good stuff on their car, but it doesn't work since diffuser doesn't work. And if it doesn't work, the whole car is in trouble.

I've seen how smallest geometry changes in diffuser can lead to separation, causing it to lose performance, causing the whole car to lose performance up to 20% almost. And this was only in CFD, in a simple steady simulation of 1/2 of car in a straight line, on a car where floor gets at most 30% of overall downforce, so imagine having a small (but big enough) change in geometry in reality and your car can't turn all of a sudden. Changing balance trough the corner and what not - sounds a lot like Williams, doesn't it?

[godlameroso]

Narcissism and arrogance are both a hell of a thing.

Yup.

Just to point out a fact that you are way oversimplifying things and that you can't just modify things willy nilly as you think.

You're right you can't, there are dozens of flow structures that get affected by small changes.

To illustrate this point, McLaren stated that they had to wait for the new nose to run the new barge boards in front of and turning vanes around the sidepods. This is because the flow structures were wrong with the old nose to work with the new parts. That's how careful teams have to be with changes.

They ran provisional versions of the new side pod end plates in Bahrain IIRC, they were hesitant to run it, but went ahead and it was a small improvement. Yes I realize and have said numerous times that they needed to introduce the new nose to develop the rest of the car. How many times have I said that the new nose would be a modest improvement and we wouldn't see them take advantage of it until France at the earliest. I know it takes a good 4-6 weeks lead time to manufacture these parts. I'm perfectly aware of the time frames, at least we seem to agree there, maybe you also agree that this is a very critical area.

[godlameroso]

New hotness from Ferrari. Seems to have worked for them, looks like everyone is developing this area now.

[godlameroso]

Mercedes has grown their chicken wing some, but no pictures to show the rest.

[godlameroso]

Looking at the Renault you see they have a lot of potential, lots of surface area in the footplate region, the thick leading edge and very tapered end keeps this area from being very draggy. They still have that plate, but with the amount of air they guide under the foot plate I don't think it's affecting them that much drag wise.

[godlameroso]

Not sure if new development on the Red Bull, but you can't deny their performance, even the Sauber has gotten better because it started messing in this area.

[godlameroso]

McLaren you need to step your game up, you're not using a big chunk of footplate surface area, look at the Sauber above, behind the bargeboard, huge surface area that McLaren has neglected. There's so much they have to do, hopefully they can bring something decent for France.

[PhillipM]

I think I mentioned it in another thread somewhere but there are some more bargeboard revisions/bits coming for France for Mclaren.

[godlameroso]

I think I mentioned it in another thread somewhere but there are some more bargeboard revisions/bits coming for France for Mclaren.

I saw, I think it's great news, I hope it works out for them. I make a big deal of this area because I feel aerodynamically the rest of the car is very good.

[godlameroso]

Old setup with crappy paint CFD.




As you can see Ferrari has added slots near the edge of the bargeboard over the mid wing, precisely to preserve the vortecies that are travelling both over and laterally across the mid wing.

[godlameroso]

Ferrari's bargeboard with a little patina flow vis.

[roon]

I don't think the trajectory of the debris flying off the tires and bouncing along the ground is a reliable indicator of airflow. Those relatively massive motes will not entrain into vortexes in the same helical trajectories as the air molecules do.

[godlameroso]

I don't think the trajectory of the debris flying off the tires and bouncing along the ground is a reliable indicator of airflow. Those relatively massive motes will not entrain into vortexes in the same helical trajectories as the air molecules do.

Look closer, at where the paint has been stripped off, not just the two elements on the mid wing but the outer end plate on the barge board. True you're not looking at stream lines but rather where the airflow tends to go.

[godlameroso]

In the lower image you can see the ground through the mid wing elements, meaning that area is being treated like a wing, with slots to delay separation.

Naturally the bargeboards force one to have a heavy angle of attack.

I still think this design, although good is not the best possible, Red Bull is the chassis with the greatest aero performance and it's no surprise as they've managed to squeeze the most surface area out of the mid wing.

Crazy right? Who'd guess that putting a wing in the middle of the car which is lower than the front wing would deliver any appreciable aero performance.

[Zynerji]

Concerning the barge board...

I'm interested in some speculation about literally putting a diffusor across the car in that area. I understand that it is all about downstream management of the flow structures, but since this is almost unlimited in this area, you could have some trick strakes in the area to still get that.

What would prevent a full blown diffusor in this area (rules), and is it worth exploring (would it help)?