Rule Interpretation - Double deck diffusers

[Conceptual]

Why, oh, why is there so much crying? Is it because it is illegal? Is it because it gives an unfair advantage? Or is it because the crybaby teams are talent deficient, and cannot think outside of the 175mm box?

I think that the Toyota and Williams interpretations are pure genius, and any team that cries should instead get some new blood in their paddock, because this is what happens when your people habitually marry their cousins.

[pipex]

I agree completely with you Conceptual, Renault should be busy trying to create a better car instead of crying because other team can exploit in a better way the regulations. Maybe they are worried because their new car is crap and don't know how to fix it .

[SLC]

Many of the reports thus far have been incorrect.

Taking advantage of the 150mm section in the centre is perfectly legal.

Crucially, it is not the presence of secondary (or even tertiary in the Toyota case) diffusing channels above the main diffuser which is of questionable legality. What is questionable, however, are the inlets to these additional air channels.

These inlets cannot lie behind the RACL (that is, in the main diffuser profile) due to 3.12.7 (specifically "Any intersection of the surfaces in this area with a lateral or longitudinal vertical plane should form one continuous line which is visible from beneath the car").

Thus, the inlets must lie ahead of the main diffuser, either as holes in the main floor surface or as holes in the vertical transition wall between the reference and step planes. Holes are allowed in this region, but you must not be able to see any part of the car above said holes when viewed from underneath (under reg 3.12.5 "Fully enclosed holes are permitted in the surfaces lying on the reference and step planes provided no part of the car is visible through them when viewed from directly below").

This would then mean you would have to have suitable cuts/holes in any bodywork above the particular region in the floor - and, here comes the important bit, you are not allowed any apertures in bodywork unless they are for exhaust flow.

The same was technically allowed in previous years - and then it was easier as there was no limitation in terms of cutting random holes in bodywork.

[SLC]

I think that the Toyota and Williams interpretations are pure genius, and any team that cries should instead get some new blood in their paddock, because this is what happens when your people habitually marry their cousins.

Aye, I'm all for innovation and clever interpretations of the rules in F1 - makes it so much more interesting for us technically minded fans.

But teams have been known (Williams on many occasions, especially with diffusers!) to interpret regs out of context allowing even the most preposterous of things to comply with the letter of the law.

[ESPImperium]

Im on the designers side, if you can get away with it, use it untill told not to by the FIA.

Personally i see no problem with the Wiliams one, it looks so simple, but purposeful. The Toyota one serves a purpose, its built into the rear crash structue, but serves a purpose.

I finally found a Ferarri F60 difuser picture:




The teal line is the 175mm line.

Im looking at other pictures at the moment and just looking at them Ferarri have posibly been testong about 2 or 3 diffrent diffuser designs, all simmilar, but diffrent in their own way. Or it just may be my eyes playing tricks on me with som poor-ish pics.

[SLC]

Again, it has nothing to do with the 175mm high rule.

The problem is where the hell are they feeding these channels? (highlighted in red)

[vasia]

Again, it has nothing to do with the 175mm high rule.

The problem is where the hell are they feeding these channels? (highlighted in red)

From as far as I can tell, the rear suspension members, the diffuser, rear crash structure, and the rear wing on the TF109 all work very closely together to control airflow and also to provide downforce.

Although I haven't seen detailed pictures of the rear end to 100% confirm this, I believe the channels are being fed from air that flows through the undercuts in the sidepods and through the suspension members to directly feed those channels. Either that, or it could be airflow that is flowing from above the sidepods and around the engine cover.

[Ciro Pabón]

Thanks, ESPImperium. Great, great post.

Nice picture, SLC. What's all that foamy water?

Smirkoff, there is a new article with the drawing you asked for. Tomba is a good webmaster... altough I shouldn't be the one saying that.

Analysis: Teams seek clarification about diffusers

The newsletter many of you probably received includes this:

A scientific approach to 2009 F1 regulations

Finally, truly interesting comments, scarbs. It's amazing to hear it straight from the horse's mouth, among so many forums full of speculations. Thanks for your time, Lone Ranger, and, please, keep posting your "Hi-yo, Silver!" posts. I bet at least one million, of the four million hits this site got last year, are because of them.

Scarbs in full attire, Sam Michael to his right. Notice the white mouse in his left hip


On a side note, I think that rules are there to be bent, never broken...

[Metar]

I think that foamy water has to be the extinguisher foam? Toyota's car caught fire, after all.

[wesley123]

I dont think the diffuser is illegal, afterall i thought the rules dont say anything about the area behind that.

[scarbs]

I believe the upper diffuser channel is similar to the little supplementary diffuser channels we saw above the side tunnels last year. As it beats both the minimum height and the single continuous curve rules.

To feed the upper part of the double deck diffuser, the middle 750mm of the lower diffuser doesn't reach the kick line where the flat floor meets the diffuser (i.e. the rear axle line). This leaves a window for the flow either side of the stepped floor to flow up into the upper deck.

The upper deck is permitted to be 25mm higher than the lower diffuser, which creates a 25 x 750 exit window, quite a gain in addition to the 175 x 1000 everyone else has.

I didn't initially realise the Toyota made use of these channels too, their early Portimao test diffuser didn't even have the 150mm middle extension. This must be the third floor they've tested in one week! No wonder Pascal was so knowing when talking to me on the first day of the test about the Williams diffuser.

[Moanlower]

There are some clear drawings and info about the differences in diffuser Toyota has compared to Mclaren and Ferrari.

http://www.formula1.com/news/technical/

[scarbs]

I did some analysis for autosport.com too

http://www.autosport.com/news/report.php/id/73083

[axle]

Unofficially legal now

http://en.f1-live.com/f1/en/headlines/n ... 3340.shtml

[myurr]

Oh well, so much for working towards overtaking. All the teams will have to develop these now, disrupting the airflow more than the cars were planned to.