A place to discuss the characteristics of the cars in Formula One, both current as well as historical. Laptimes, driver worshipping and team chatter do not belong here.
- for any given ride height it reduces overall floor downforce, therefore increasing the velocity at which it might occur
- simply by being higher it prevents the choking from occuring, but this alone is not always the only cause for floor stall that start the bouncing
Raising the floor edges reduces mechanical and vortice sealing of the floor, therefore again reducing overall floor downforce and increasing the speed at which bouncing starts. With significant gains in solving this problem during 2022, there is no reason to expect any team will have significant issues with bouncing.
This alone hurts RB and Ferrari the most, as their relative advantage to the rest of the field will be cut significantly. Performance/downforce loss that also comes with changes will also be more benefitial for teams that didn't solve the bouncing without sacrificing performance. So yeah, no wonder Ferrari and RB were pissed with Merc pushing the safety "issues" to reduce the performance gap.
- for any given ride height it reduces overall floor downforce, therefore increasing the velocity at which it might occur
- simply by being higher it prevents the choking from occuring, but this alone is not always the only cause for floor stall that start the bouncing
Raising the floor edges reduces mechanical and vortice sealing of the floor, therefore again reducing overall floor downforce and increasing the speed at which bouncing starts. With significant gains in solving this problem during 2022, there is no reason to expect any team will have significant issues with bouncing.
This alone hurts RB and Ferrari the most, as their relative advantage to the rest of the field will be cut significantly. Performance/downforce loss that also comes with changes will also be more benefitial for teams that didn't solve the bouncing without sacrificing performance. So yeah, no wonder Ferrari and RB were pissed with Merc pushing the safety "issues" to reduce the performance gap.
Plain and simple explanation
See you on the winter tests
The plank is still in the same spot. The throat and the floor edge have been raised 15mm ...
Yeah, for sure you are right, but i said you can also view it a bit different.
If you fully raise a 22 car 15 mm, the difference compared to a 23 car is that the plank is 15 lower in the latter.
In 22, the plank and floor edge (if you ignore flexible floors) are in rougjly the same plane. There are many reasons to have the entire floor a bit raised.
If you push a rule to lift the floor edges, making them higher than the plane of the plank, teams may find they'd like the floor edge lower than '22 +15mm', resulting in an incentive to have the plank very close to the asphalt. Maybe even very stiff suspension again to get the floor low in low speed corners.
That is all well and good henrik but which team has the most experience / ability to deal with this? Which team has been most successful with sealing the floor with a high ride height / floor edge with either overbody or underbody options?
Then ask which team has always preferred to run there car close to the ground in either the new or old regulations?
The plank is still in the same spot. The throat and the floor edge have been raised 15mm ...
Yeah, for sure you are right, but i said you can also view it a bit different.
If you fully raise a 22 car 15 mm, the difference compared to a 23 car is that the plank is 15 lower in the latter.
In 22, the plank and floor edge (if you ignore flexible floors) are in rougjly the same plane. There are many reasons to have the entire floor a bit raised.
If you push a rule to lift the floor edges, making them higher than the plane of the plank, teams may find they'd like the floor edge lower than '22 +15mm', resulting in an incentive to have the plank very close to the asphalt. Maybe even very stiff suspension again to get the floor low in low speed corners.
There's no incentive to bottom out the plank due to the plank deflection and wear regulations. Teams already run the ride height at the point where they can pass the plank wear legality after a 90 minute race. Moving the throat and floor edge makes no difference to this because the plank is still the low point and will only tolerate a certain amount of bottoming.
Are you sure? There were many ride height strategies and ride height differences between teams. If all teams ran as low as the plank allowed, why those differences? Some teams ran low and stiff around the track, some teams ran high and had their cars squat low in the straight. There were obviously more parameters than just plank wear, at least in the medium/slow corners.
Wearing your plank at the end of the straight or in slow corners are two different things.
Just wondering if the new regs might backfire and have teams that ran high and soft to go low and stiff.
The plank is still in the same spot. The throat and the floor edge have been raised 15mm ...
Yeah, for sure you are right, but i said you can also view it a bit different.
If you fully raise a 22 car 15 mm, the difference compared to a 23 car is that the plank is 15 lower in the latter.
In 22, the plank and floor edge (if you ignore flexible floors) are in rougjly the same plane. There are many reasons to have the entire floor a bit raised.
If you push a rule to lift the floor edges, making them higher than the plane of the plank, teams may find they'd like the floor edge lower than '22 +15mm', resulting in an incentive to have the plank very close to the asphalt. Maybe even very stiff suspension again to get the floor low in low speed corners.
There's no incentive to bottom out the plank due to the plank deflection and wear regulations. Teams already run the ride height at the point where they can pass the plank wear legality after a 90 minute race. Moving the throat and floor edge makes no difference to this because the plank is still the low point and will only tolerate a certain amount of bottoming.
If the 'sparkers' are set correctly, bottoming out does not need the plank to rub. It could even be possible to lock suspension movement before the point the plank hits the ground. There would obviously be some due to high points on the track.
When arguing with a fool, be sure the other person is not doing the same thing.
Yeah, for sure you are right, but i said you can also view it a bit different.
If you fully raise a 22 car 15 mm, the difference compared to a 23 car is that the plank is 15 lower in the latter.
In 22, the plank and floor edge (if you ignore flexible floors) are in rougjly the same plane. There are many reasons to have the entire floor a bit raised.
If you push a rule to lift the floor edges, making them higher than the plane of the plank, teams may find they'd like the floor edge lower than '22 +15mm', resulting in an incentive to have the plank very close to the asphalt. Maybe even very stiff suspension again to get the floor low in low speed corners.
There's no incentive to bottom out the plank due to the plank deflection and wear regulations. Teams already run the ride height at the point where they can pass the plank wear legality after a 90 minute race. Moving the throat and floor edge makes no difference to this because the plank is still the low point and will only tolerate a certain amount of bottoming.
If the 'sparkers' are set correctly, bottoming out does not need the plank to rub. It could even be possible to lock suspension movement before the point the plank hits the ground. There would obviously be some due to high points on the track.
There's no incentive to bottom out the plank due to the plank deflection and wear regulations. Teams already run the ride height at the point where they can pass the plank wear legality after a 90 minute race. Moving the throat and floor edge makes no difference to this because the plank is still the low point and will only tolerate a certain amount of bottoming.
If the 'sparkers' are set correctly, bottoming out does not need the plank to rub. It could even be possible to lock suspension movement before the point the plank hits the ground. There would obviously be some due to high points on the track.
The sparkers are banned for '23.
Are they? good. Will there still be 'stubs' to prevent grinding the bottom off? You know, a carelessly designed bolt an inch too long?
When arguing with a fool, be sure the other person is not doing the same thing.
If the 'sparkers' are set correctly, bottoming out does not need the plank to rub. It could even be possible to lock suspension movement before the point the plank hits the ground. There would obviously be some due to high points on the track.
The sparkers are banned for '23.
Are they? good. Will there still be 'stubs' to prevent grinding the bottom off?
Well normally a team (like we saw at Mercedes and Mclaren I believe), will add some metal stripping to the floor edge. Otherwise, the plank IS the wear component, not the floor edge.
Are they? good. Will there still be 'stubs' to prevent grinding the bottom off?
Well normally a team (like we saw at Mercedes and Mclaren I believe), will add some metal stripping to the floor edge. Otherwise, the plank IS the wear component, not the floor edge.
If they have to design to actually meet the spec it could have some 'side effects' then
When arguing with a fool, be sure the other person is not doing the same thing.
Are they? good. Will there still be 'stubs' to prevent grinding the bottom off?
Well normally a team (like we saw at Mercedes and Mclaren I believe), will add some metal stripping to the floor edge. Otherwise, the plank IS the wear component, not the floor edge.
If they have to design to actually meet the spec it could have some 'side effects' then
Any car designed to the "spirit" of the regulation is going to be slower as a "side effect"
The changes to the floor regulations are interesting. I wonder if the higher floor edge and stricter floor flexing tests will cause the ice skate to be less advantageous. Maybe we will see more 'proper' floor edge wings in 2023 instead of ice skates.
I also wonder how much the higher diffuser throat will impact the packaging of the gearbox and rear suspension. Could this make rear pushrods more advantageous?
All pure speculation on my part - but I guess that's the point of the thread. I'd love to hear what the forum experts think.
- for any given ride height it reduces overall floor downforce, therefore increasing the velocity at which it might occur
- simply by being higher it prevents the choking from occuring, but this alone is not always the only cause for floor stall that start the bouncing
Raising the floor edges reduces mechanical and vortice sealing of the floor, therefore again reducing overall floor downforce and increasing the speed at which bouncing starts. With significant gains in solving this problem during 2022, there is no reason to expect any team will have significant issues with bouncing.
This alone hurts RB and Ferrari the most, as their relative advantage to the rest of the field will be cut significantly. Performance/downforce loss that also comes with changes will also be more benefitial for teams that didn't solve the bouncing without sacrificing performance. So yeah, no wonder Ferrari and RB were pissed with Merc pushing the safety "issues" to reduce the performance gap.
As was explained by Jean-Claude Migeot—in the various articles published early last season regarding porpoising—stalled flow is not the cause of the porpoising. It should also be considered that though teams can’t simulate the dynamics of porpoising in the WT they can nevertheless run the model at very low ground clearance and so would have assessed any choking/stalling issues. Indeed, the team with the worst bouncing car early on—the Mercedes—were trying to run the car as low as possible.
The whole issue of porpoising is really one of aeroelasticity—the interaction of aero, inertia and elastic (suspension) forces.
Aerodynamically, the issue was likely due to the non-linear increase in DF at low ride heights (from floor edge sealing, possibly with an out-of-phase frequency) and disruption to this sealing causing loss in DF. The unsteady DF resulting from this, when combined with the harmonic motion of sprung and suspension elasticity combined was likely the cause of the porpoising. Hence the teams’ efforts to stiffen floors (and their edges) and the FIA’s efforts to raise the floor edges.
As was explained by Jean-Claude Migeot—in the various articles published early last season regarding porpoising—stalled flow is not the cause of the porpoising. It should also be considered that though teams can’t simulate the dynamics of porpoising in the WT they can nevertheless run the model at very low ground clearance and so would have assessed any choking/stalling issues. Indeed, the team with the worst bouncing car early on—the Mercedes—were trying to run the car as low as possible.
The whole issue of porpoising is really one of aeroelasticity—the interaction of aero, inertia and elastic (suspension) forces.
Aerodynamically, the issue was likely due to the non-linear increase in DF at low ride heights (from floor edge sealing, possibly with an out-of-phase frequency) and disruption to this sealing causing loss in DF. The unsteady DF resulting from this, when combined with the harmonic motion of sprung and suspension elasticity combined was likely the cause of the porpoising. Hence the teams’ efforts to stiffen floors (and their edges) and the FIA’s efforts to raise the floor edges.
First of all, I'm fairly certain that Migeot either wasn't correctly quoted or misspoke about stalled flow and bouncing, especially since there were a lot of other stall "statements" that were plain wrong (like the one where floor stall does not have a dynamic impact on the car). Journos also often use stall and choke interchangeably and this is plain wrong.
Choking the tunnels possibly happened to launch-spec floor of Mercedes as it had a very low tunnel height (vs RB and Ferrari particularly) and they had very violent bouncing at times, even with raised ride height. Stall of diffuser alone is second possibility, but this is highly unlikely alone since teams usually have the diffuser kick higher than the throat of the tunnels (RB seems to be the only exception). Choking the tunnels is one of the causes of stalled flow, but is not the only reason. Stalled flow can be one of the triggers for bouncing, but is not the only trigger.
Diffuser fences are particularly important for diffuser performance and there can be a low ride height case when the vortices from floor edges and tyre squirt mess up the flow so bad that diffuser itself can have areas with stalled flow. Or, at the very least, strong loss of performance due to huge loss of energy coming from turbulent flow entering diffuser. Kyle gave a very comprehensive explanation in his video, it was posted on other threads as well.
Due to non-active nature of suspension, very high floor downforce can cause problems alone and suspension reaction to it (e.g. aggressive bump stop rebound) can trigger the bouncing - so in theory reducing the downforce potential trough rules can help solve the bouncing problem. There are several other important things to note as well. Regarding the model he used for CFD, it's early spec Sauber and Sauber always had a relatively high floor throat, so drawing conclusions that there is no floor stall on any car is wrong.
Other than that, stall can happen as a dynamic phenomenon coming from bouncing itself - where vertical floor movement introduces another vertical flow velocity component that isn't there without bouncing that causes the stall. So bouncing can be triggered by an aggressive bump-stop hit (e.g.) and then get amplified by resulting flow stall. This was mentioned to one of the posters here from a Mercedes aerodynamicist.
So bouncing is a very complex phenomenon and different teams likely had to apply different solutions to solve it. Mercedes actually didn't fully solve it in the end, it was still causing them problems in Abu Dhabi as well. However, seeing how a lot of work was put into floor edge treatment, we can assume these edge vortices were one of the more important areas for overall floor performance (including a solution for bouncing).
To conclude and reiterate - raising floor edges in 2023 will reduce downforce potential and raising the throat will both reduce downforce potential and can also prevent choking from ever occurring on any car in any attitude on track at any speed. If not fully prevented, than at least the number of scenarios where choking can occur will be significantly reduced.
