2022 cars 'porpoising' at high speed

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NtsParadize
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Re: ‘porpoising’…

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shamyakovic wrote:
Thu Feb 24, 2022 9:25 pm
Would a 2006 style mass damper help the situation?
Yes

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DiogoBrand
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Re: ‘porpoising’…

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Are bumpstops allowed in F1? I mean, a team could setup the suspension to not compress enough to stall and it would resolve the issue.

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Zynerji
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Re: ‘porpoising’…

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DiogoBrand wrote:
Thu Feb 24, 2022 9:50 pm
Are bumpstops allowed in F1? I mean, a team could setup the suspension to not compress enough to stall and it would resolve the issue.
Packers?

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RicerDude
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Re: ‘porpoising’…

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NtsParadize wrote:
Thu Feb 24, 2022 9:42 pm
shamyakovic wrote:
Thu Feb 24, 2022 9:25 pm
Would a 2006 style mass damper help the situation?
Yes
Weren’t the mass dampers more effective at cancelling our lower amplitude vibrations, like running over kerbs? To cancel out the kind of porpoising we’ve been seeing, you’d need a pretty heavy mass damper wouldn’t you?

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DiogoBrand
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Re: ‘porpoising’…

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shamyakovic wrote:
Thu Feb 24, 2022 9:25 pm
Would a 2006 style mass damper help the situation?
It would alleviate the effect but not cure the cause of the issue.

Hoffman900
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Re: ‘porpoising’…

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DiogoBrand wrote:
Thu Feb 24, 2022 9:50 pm
Are bumpstops allowed in F1? I mean, a team could setup the suspension to not compress enough to stall and it would resolve the issue.
This should be controlled by the heave spring, which is a better way of doing it, but also how push/pull rod suspensions work in general, at least in the rear.

A bump stop is also a spring, it can be progressive or have a rate equal to that of whatever it is resting against :lol:
Last edited by Hoffman900 on Thu Feb 24, 2022 10:03 pm, edited 1 time in total.

Hoffman900
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Re: ‘porpoising’…

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RicerDude wrote:
Thu Feb 24, 2022 9:53 pm
NtsParadize wrote:
Thu Feb 24, 2022 9:42 pm
shamyakovic wrote:
Thu Feb 24, 2022 9:25 pm
Would a 2006 style mass damper help the situation?
Yes
Weren’t the mass dampers more effective at cancelling our lower amplitude vibrations, like running over kerbs? To cancel out the kind of porpoising we’ve been seeing, you’d need a pretty heavy mass damper wouldn’t you?
Likely. You want to tune out the amplitude in which it is porpoising at.

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godlameroso
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Re: ‘porpoising’…

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Using suspension to cure this is like using the American healthcare model. You just want a patch that just suppresses the symptoms and doesn't address the root cause. This is a poor approach unless you want repeat customers.
Saishū kōnā

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DiogoBrand
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Re: ‘porpoising’…

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godlameroso wrote:
Thu Feb 24, 2022 10:04 pm
Using suspension to cure this is like using the American healthcare model. You just want a patch that just suppresses the symptoms and doesn't address the root cause. This is a poor approach unless you want repeat customers.
What other way do you have of solving it that doesn't involve a loss in max downforce?
(And is within the rules)
Last edited by DiogoBrand on Thu Feb 24, 2022 10:06 pm, edited 1 time in total.

dialtone
dialtone
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Re: ‘porpoising’…

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Speaking without experience on the topic...

Some teams are opening cuts in the floor edge quite crudely. Do you think it could be an attempt to help with this effect? I'd imagine that with a fixed section inlet but a variable section tunnel and exit it can get to a point where the air that goes in can't find a way out and starts to act as a pillow instead at that speed, especially if cars get to negative rake territory. Opening up pieces in the floor could create areas where under pressure the flow can escape and avoid chocking the floor.

Hoffman900
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Re: ‘porpoising’…

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godlameroso wrote:
Thu Feb 24, 2022 10:04 pm
Using suspension to cure this is like using the American healthcare model. You just want a patch that just suppresses the symptoms and doesn't address the root cause. This is a poor approach unless you want repeat customers.
Race cars are a series of compromises.

If the ability to control rear ride height is the issue, then the suspension is absolutely the solution.

If the issue is vortex shearing causing a resonance, then yes, it isn’t the sole solution, but it may be a combination of suspension and aero.

Same goes for choke flow caused by flow separations.

It’s an entire package.
Last edited by Hoffman900 on Thu Feb 24, 2022 10:11 pm, edited 1 time in total.

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godlameroso
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Re: ‘porpoising’…

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DiogoBrand wrote:
Thu Feb 24, 2022 10:06 pm
godlameroso wrote:
Thu Feb 24, 2022 10:04 pm
Using suspension to cure this is like using the American healthcare model. You just want a patch that just suppresses the symptoms and doesn't address the root cause. This is a poor approach unless you want repeat customers.
What other way do you have of solving it that doesn't involve a loss in max downforce?
(And is within the rules)
You modify the floor to reduce the likely hood of flow detachment. Particularly at the bow, and the diffuser. Alpine proved that you can mitigate stalling at the diffuser with a supplemental air stream. Alpha Tauri had little to no porpoising, and McLaren largely avoided the issue as well. Look at their floors and analyze how they are different to Mercedes, AMR, Ferrari, Alpine, and the other bouncy bois. The bouncy bois all have sharp axe bows, the non bouncy bois have blunted, more bulbous bows, and in the case of McLaren they channel the bow wake over and around the tunnel inlet.
Saishū kōnā

Hoffman900
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Re: ‘porpoising’…

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godlameroso wrote:
Thu Feb 24, 2022 10:11 pm
DiogoBrand wrote:
Thu Feb 24, 2022 10:06 pm
godlameroso wrote:
Thu Feb 24, 2022 10:04 pm
Using suspension to cure this is like using the American healthcare model. You just want a patch that just suppresses the symptoms and doesn't address the root cause. This is a poor approach unless you want repeat customers.
What other way do you have of solving it that doesn't involve a loss in max downforce?
(And is within the rules)
You modify the floor to reduce the likely hood of flow detachment. Particularly at the bow, and the diffuser. Alpine proved that you can mitigate stalling at the diffuser with a supplemental air stream. Alpha Tauri had little to no porpoising, and McLaren largely avoided the issue as well. Look at their floors and analyze how they are different to Mercedes, AMR, Ferrari, Alpine, and the other bouncy bois. The bouncy bois all have sharp axe bows, the non bouncy bois have blunted, more bulbous bows, and in the case of McLaren they channel the bow wake over and around the tunnel inlet.
Did they mitigate it?

I believe we’re lacking data to definitely say whether they all did or not, and I believe it is reported it still exists at some magnitude on all of them.

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godlameroso
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Re: ‘porpoising’…

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Hoffman900 wrote:
Thu Feb 24, 2022 10:10 pm
godlameroso wrote:
Thu Feb 24, 2022 10:04 pm
Using suspension to cure this is like using the American healthcare model. You just want a patch that just suppresses the symptoms and doesn't address the root cause. This is a poor approach unless you want repeat customers.
Race cars are a series of compromises.

If the ability to control rear ride height is the issue, then the suspension is absolutely the solution.

If the issue is vortex shearing causing a resonance, then yes, it isn’t the sole solution, but it may be a combination of suspension and aero.

Same goes for choke flow caused by flow separations.

It’s an entire package.
The suspension is not an ideal solution, it's A solution. If you are forced to use bump stops to keep the car from bottoming out it still doesn't change the car behavior if it's being caused by aero instability. If you limit suspension travel so the car doesn't get too low, then you also limit suspension travel over bumps, you also limit grip at low speed corners. Whereas if you solve the issue from an aero perspective you free the suspension to work in a greater range of conditions. This is why solving the root issue is the way to go in the long run.
Saishū kōnā

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godlameroso
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Re: ‘porpoising’…

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Hoffman900 wrote:
Thu Feb 24, 2022 10:13 pm
godlameroso wrote:
Thu Feb 24, 2022 10:11 pm
DiogoBrand wrote:
Thu Feb 24, 2022 10:06 pm


What other way do you have of solving it that doesn't involve a loss in max downforce?
(And is within the rules)
You modify the floor to reduce the likely hood of flow detachment. Particularly at the bow, and the diffuser. Alpine proved that you can mitigate stalling at the diffuser with a supplemental air stream. Alpha Tauri had little to no porpoising, and McLaren largely avoided the issue as well. Look at their floors and analyze how they are different to Mercedes, AMR, Ferrari, Alpine, and the other bouncy bois. The bouncy bois all have sharp axe bows, the non bouncy bois have blunted, more bulbous bows, and in the case of McLaren they channel the bow wake over and around the tunnel inlet.
Did they mitigate it?

I believe we’re lacking data to definitely say whether they all did or not, and I believe it is reported it still exists at some magnitude on all of them.
McLaren was running slammed since day one and they did experience it but not to the extent of the bouncy boi crew.

Alpine's solution worked pretty well for them, and they basically just copied what AT was doing with their floor...but with a dremel or hacksaw or some primitive cutting tool. So it wasn't ideal for them.
Saishū kōnā