What stands out on the straight here: Some of the cars are very bumpy. Especially the Williams, but also the Aston Martin and the Alpine. On the Aston, it disappears when DRS is open. Red Bull stable, right up to the braking zone. Ferrari, Merc and AlphaTauri don't bounce at all. #F1
There is a problem with aerodynamic bounce, with teams trying to flex the bottom to maximize ground effect. The pre-season of the new era of Formula 1 has officially begun. The only thing missing was the Red Bull RB18. Now we know for sure: the new cars are a complete break from what we've been used to seeing in recent seasons.
Bulkier nose and bellies, front wings more raised from the ground, more compact rear vents and, above all, mechanics, on several cars, completely overturned.
F1 2022: ground effect does not only bring advantages
This 2022 season must be seen as a new beginning. Teams will still be able to take advantage of previous knowledge and, to some extent, old aerodynamic concepts, but they will have to apply them in a rather different way.
We have defined them as "ground effect" single-seaters, because the bottom of the car will have two long "converging-diverging" tunnels that, through the Venturi effect, will glue them to the ground. The way in which cars generate aerodynamic load has been totally modified. It will count more the bottom and less the ailerons.
This will lead to a significant increase in the efficiency of the cars. The new cars will therefore be faster in a straight line, at the level of the previous generation in fast corners, while the understeer and the 795 kg, will put them in more difficulty in the mixed and slow.
However, the ground effect also has criticalities. One of these is the risk that the car, once it has passed a certain speed, begins to bounce. A phenomenon deriving from an accentuated aerodynamic instability due to important problems of airflow separation.
As far as Formu1a.uno understands, this is what happened to at least one team on the filming day, used to wean off the new single-seater, and to Alfa Romeo on the morning of the first day of pre-season testing.
To the particular team that suffered during the filming day carried out last week, the phenomenon occurred beyond 250 km/h. The car was as if it went into resonance, starting to jump and also leading to problems with cracks in the lower part of the bottom.
F1 2022: teams try to make the bottom flex at high speeds
Teams are trying to run as close to the asphalt as possible, especially at high speeds, to maximize ground effect. However, it's a very efficient load-generating phenomenon but can be extremely sensitive to pitch, yaw and roll of the car.
To seal the outside of the bottom even more and to try to recreate an effect similar to the mini-skirts in the wing cars of the 1980s, teams are trying to flex the outer parts of the bottom. Getting too close to the ground, however, poses major risks of flow separation.
One engineer let us know that on this new generation of cars, a change of even a few mm in ground clearance in the fast setting results in a drastic decrease in downforce.
If the flow were to detach, with a loss of aerodynamic load, the car would tend to rise because the springs would no longer be compressed by the vertical thrust generated by the aerodynamic load. The car rising, would favor again the flow reattachment and therefore an increase in the generation of aerodynamic load. The car would be again closer to the ground. This would cause a new separation and so on with a car that would continue to bounce. This has happened to at least two teams.
The team that had this problem during the filming day, managed today to contain it thanks to a stiffening in the outer part of the bottom and working on the mechanical setup.
Author: Piergiuseppe Donadoni
Translated with www.DeepL.com/Translator (free version)
That is very interesting. Somewhat worrying for the A522.RedNEO wrote: ↑24 Feb 2022, 02:23What stands out on the straight here: Some of the cars are very bumpy. Especially the Williams, but also the Aston Martin and the Alpine. On the Aston, it disappears when DRS is open. Red Bull stable, right up to the braking zone. Ferrari, Merc and AlphaTauri don't bounce at all. #F1
Bumpy car is good forventuri if done right. Flow attachments as floor is moving with the shape of the ground.AR3-GP wrote: ↑24 Feb 2022, 03:07That is very interesting. Somewhat worrying for the A522.RedNEO wrote: ↑24 Feb 2022, 02:23What stands out on the straight here: Some of the cars are very bumpy. Especially the Williams, but also the Aston Martin and the Alpine. On the Aston, it disappears when DRS is open. Red Bull stable, right up to the braking zone. Ferrari, Merc and AlphaTauri don't bounce at all. #F1
The first day of testing the new cars showed the pitfalls of the new technology. If you drive with too little ground clearance, you run the risk of bottoming out on the straights. Then the car starts pumping.
Ground effect cars prefer it low. The better the wing profile is sealed in the ground towards the sides, the more contact pressure it generates. And downforce increases with speed. But that can be a trap on the straights. If the car is too low, so much downforce is generated from a certain speed that the ground touches the road.
This creates an effect that can be described as pumps. When it hits the ground, the downforce breaks off and the car comes up again. The process repeats itself with increasing speed. The racing cars then literally hop down the straights at top speed.
Some drivers struggled to keep their cars on the road. On his film day, Haas couldn't go faster than 250 km/h on the home stretch. The US Ferrari rocked so much that he practically jumped.
Also on the first day of testing, the so-called "bouncing" occupied the engineers of the American racing team. The underbody was damaged, which led to long downtimes. Also at Alfa Romeo a fastening of the floor broke. Just repairing it didn't make sense. Before the next trip, the engineers racked their brains about what caused the problem and how to alleviate or fix it.
Looking for a compromise solution
Haas was not alone in his worries. Alfa Romeo, Williams, Aston Martin, Alpine and Mercedes also touched down and rocked on the home straight. Ferrari and McLaren were least affected. Factors such as ground clearance and suspension travel play a role in the phenomenon.
"We still have a lot to learn about the setup," confirms Haas team boss Guenther Steiner. "We're looking for the happy medium. Not too low, so that the car doesn't touch down, but not too high, so that too much downforce is lost." Mercedes team boss Toto Wolff sums it up: "The key to fast laps is to drive as low as possible and still have the problem of bouncing under control. Ferrari and McLaren are currently the best at it."
Alpine Operations Manager Alan Permane points out: "We haven't driven this low for ages. The cars are practically no longer employed. It's a puzzle of factors that can lead to bouncing. To find out, we went through many different set-ups ."
Back to classic dampers
At Aston Martin, they believe that the flexibility of the floor also plays a role. "The rocking has not announced itself in the wind tunnel. This means that it is not a purely aerodynamic problem," says an Aston Martin technician. Other teams are of the same opinion. "With Haas and Alfa Sauber, the outer edges of the floor bend more than with others. That's why the bouncing is also more pronounced with them."
When it comes to spring comfort, the engineers have to cope with two new framework conditions. Pirelli's 18-inch tires flex less than their predecessors. And in the chassis, hydraulic damping elements, mass inertia dampers and remote dampers have been banned since this year. Formula 1 is returning to the classic telescopic dampers with coil springs or torsion bars.
This means that it is no longer possible to lower the car when the load increases, as Mercedes, for example, did to the extreme last year. Nor would it be desirable. With ground effect cars, you'd rather go a little higher on the straights.
In the picture gallery we explain the bouncing phenomenon using photos from Barcelona.
Click here to go to the source article Note: Article is in German
Didnt Mclaren also opt for old style sidepods?Andi76 wrote: ↑24 Feb 2022, 13:50There are reports in the German Media and pictures on the internet that the Mercedes and Williams cars are "wobbling". Probably they have an aerodyamical problem and the air is stalling in waves somewhere. Interesting about this is that Mercedes and Williams seem to have that specific problem. Both have opted for the "old-style 2021"-sidepod design. Did Mercedes and Williams screw-up by staying with the old "short-sidepod"-style solution?
No one part is a magic bullet, it would be surprising if the sidepods were the key factor in how the floor behaves.Andi76 wrote: ↑24 Feb 2022, 13:50There are reports in the German Media and pictures on the internet that the Mercedes and Williams cars are "wobbling". Probably they have an aerodyamical problem and the air is stalling in waves somewhere. Interesting about this is that Mercedes and Williams seem to have that specific problem. Both have opted for the "old-style 2021"-sidepod design. Did Mercedes and Williams screw-up by staying with the old "short-sidepod"-style solution?
