Red Bull RB9 Renault

[DaveW]

Goal: Race a splitter system that can bend more easily than it does while being FIA tested.

Suppose the splitter plate IS the front 3rd spring - a leaf spring cantilevered forward of the tub, connected to the front suspension by the stay acting as a pure tension element.

The plate would surely be stiff enough to survive the FIA test, the plate would be deflected away from the road as down force increases, a slight negative preload might explain any stay "buckling" at full droop, and the stay "whipping" over kerbs might also be expected.

Just a thought....

[bhall]

Goal: Race a splitter system that can bend more easily than it does while being FIA tested.

Suppose the splitter plate IS the front 3rd spring - a leaf spring cantilevered forward of the tub, connected to the front suspension by the stay acting as a pure tension element.

The plate would surely be stiff enough to survive the FIA test, the plate would be deflected away from the road as down force increases, a slight negative preload might explain any stay "buckling" at full droop, and the stay "whipping" over kerbs might also be expected.

Just a thought....

That would make the system a form of reactive ride height, correct?

This is easily the most plausible explanation I've seen thus far.

[trinidefender]

Goal: Race a splitter system that can bend more easily than it does while being FIA tested.

Suppose the splitter plate IS the front 3rd spring - a leaf spring cantilevered forward of the tub, connected to the front suspension by the stay acting as a pure tension element.

The plate would surely be stiff enough to survive the FIA test, the plate would be deflected away from the road as down force increases, a slight negative preload might explain any stay "buckling" at full droop, and the stay "whipping" over kerbs might also be expected.

Just a thought....

That would make the system a form of reactive ride height, correct?

This is easily the most plausible explanation I've seen thus far.

That is all well send dandy but you all are forgetting a key factor. If that were true then the force on the front of the splitter would be easily enough to wear the plank well past legal limits.

I just thought of another scenario, however judging by the buckling support it seems unlikely. What if, instead of the support being under compression, it is under tension. What I mean is if they have managed to make the floor strong enough that it doesn't actually need the support. Then place the support under tension. Combine this with a resin that softens slightly when it heats up, it will cause the support to pull the front of the splitter up because oft he tension placed on the support.

This however doesn't explain how the floor passed the load tests

[DaveW]

That is all well send dandy but you all are forgetting a key factor. If that were true then the force on the front of the splitter would be easily enough to wear the plank well past legal limits.

Possibly.

However, the splitter geometry could be arranged not to impact the ground in steady state conditions (I guess it would not be too hard to tailor the average ride height with airspeed if that helped aero). Also the array of bolts surrounding the stay should help to limit wear in transients. Finally, the splitter spring could always be run in combination with conventional third springs....

I suspect that the ad hoc heating test was intended to expose temperature sensitive solutions.

[Matt Somers]

Have another look at my article, I made further observations from re-watching the Hungarian GP yesterday and updated the article... The splitter looks like it can pass the deflection test without the stay, however as I also pointed out neither RBR was tested post race for Skid Block Thickness. This is extremely disappointing seeing as both stays failed on the RB9's in that race it is however where the insinuation that they were heating the splitter arose from within the teams I believe and moreover the reason the FIA/FOM probably mounted the thermal camera looking backwards on Webber's car (note the patch of black paint missing from the upper metal surface of Webber's splitter in the last picture)

http://somersf1.blogspot.co.uk/2013/11/ ... rstay.html

[DaveW]

Have another look at my article

Thanks for the pointer.

I have (looked) and I don't have much to add, except to correct the assertion that an Inerter is a "legal version" of the Mass Damper. The two devices are quite different, and are/were used for quite different purposes (on the front axle of an F1 vehicle, anyway).

Personally, I find it difficult to believe that the stay/splitter resonance has any part to play in controlling the front tyres. However, your article does appear to have established is the idea of the splitter plate being the (only) 3rd spring is probably incorrect. So thanks for that.

[Matt Somers]

I can also say that although Mark's didn't display the same issues as Seb's with the stays broken (probably much more to do with their driving style) in slow motion Seb's car looked like a shopping trolley with a wonky wheel. Now this probably had quite a bit to do with the broken Endplate/Cascade upsetting the car's natural harmonics (broken in the contact with Jenson) but he seemingly was fighting with the car more than ever and breaking traction in several key zones. His stay didn't break til later in the race (first visual sign of it I got was on lap 54) and I think was caused by the in balance of the car.

[lio007]

here are some pic's of connections/connectors, that other teams use: so Ferrari and Sauber use a similar one like RB

[shelly]

So the splitter and the nose are flexible (as known) but they do not flex because of aero load; they are pulled by cables connected to the suspension so that the aero surfaces are always in the same height with respect to the front wheel.
Pre-load in the connecting system allows passing the fia tests.
Too compliant tyres do not allow the system to work well because the tyres deflection to suspenion travel ratio is too high

[Yurasyk]

Actually, RB used a metallic stay in previous seasons and at Monaco GP they started using bolts/screws/holes in the splitter and a hinge connection of the stay. But domination started a bit later.
For example

Webber's RB7 at Abu Dhabi with broken stay
hehe, another picture:

Nurburgring. Here we can see some well known dots around the stay.

[marcush.]

not intending to dwell too much on it but :
Steve Nevey of RB has admitted to building huge expertise on generating flex to help aero a loooong time ago and i always had the suspicion RedBull was already into chassis flex to help aero in 2009/10

"There are rule restrictions to limit this, but multi-physics coupling of these effects allows us to legally enhance the performance of deformable components, for example to optimise down-force and drag characteristics for flexible wing components"


source:
http://www.racecar-engineering.com/news ... imulation/

so no need for cables or levers -they "simply" design the flex into the tub to acomodate a degree of wanted bend into it .
Put in different loads through different paths and nothing really happens. The tray test is not defined vs suspension travel

[Manoah2u]

so, if other teams have something 'similar' to RB [the stay], is there evidence the competition's stay actually flexes???

[DaveW]

source:

Impressive reference Marcus, thank you for that. RBR is definitely doing something right.

I would appear that the splitter/stay design is a developing story. Do you think that the "braking stay syndrome" is deliberate feature, perhaps to change the dynamic characteristics as fuel is burned off, or just a step too far? Either way, it certainly wasn't a show-stopper.

[Richard]

Steve Nevey of RB ...

That's a brilliant quote, thanks.

[DaveW]

RB is using tea tray to mimic the Renault "mass damper" .

The evidence for that is?

Apologies, but there are good reasons why I think that is not the case.