2009 design concepts

[Scotracer]

fazit: the cars will look less appealing, the turbulence will still be relatively high and passing will still be difficult but a bit better.

That's pure speculation.

The wake structure will be similar, the strength of turbulence not.

After that, the question is to know if the teams will really make cars that follow the OWG lines. But you can't say anything before you see it.

On the plans, the turbulence will be drastically reduced.

But turbulence was never the only problem.

that is by no means speculation. the problem of dirty air is directly related to downforce. it is proportional. you can argue about the benign effects of certain types of downforce elements but in the end more downforce means more dirty air. perhaps some cars have less drag and turbulence and have different turbulence patterns but that isn't going to overrule the efect of 1 ton more or less downforce. so with pretty good accuracy you can predict that a 15% reduction in downforce and some changes in the devices that produce the downforce you are not going to make the improvement in passing that a 50% planned reduction had brought. if you can defeat that logic tell me how.

Well that suggests that the OWG/FIA had the same geometric regulations as the current regulations when they made the 50% target. Remember a diffuser has a really high lift/drag ratio; and the diffuser next year is so much larger than this year.

[johnbeamer]

Remember a diffuser has a really high lift/drag ratio; and the diffuser next year is so much larger than this year.

Given the central section is much smaller next year the size (volume) of the diffuser will be less than it is this year.

[Ogami musashi]

that is by no means speculation. the problem of dirty air is directly related to downforce. it is proportional. you can argue about the benign effects of certain types of downforce elements but in the end more downforce means more dirty air.

That's totally false.

The strength of turbulence behind a car is not related to downforce but to design.
When you have one design, it is true the strength of the vortex increases with speed (and thus downforce) but the turbulence factor not.
You can have way more downforce without all the turbulence simple, replace a tiny high camber wing by a wide, large flatter or thicker one and you'll end up with far less turbulence.

With this you can add the importance of the wake structure.

And this is even more incorrect considering the detrimental effects on the following car are dependent on the sensitivity of the airfoils.

perhaps some cars have less drag and turbulence and have different turbulence patterns but that isn't going to overrule the efect of 1 ton more or less downforce. so with pretty good accuracy you can predict that a 15% reduction in downforce and some changes in the devices that produce the downforce you are not going to make the improvement in passing that a 50% planned reduction had brought. if you can defeat that logic tell me how.

That's not a logic, that's a statement.

You always have the example of the venturi channels that produces much more downforce without having any problems.

As i said, the problems with actual airfoils is that they are run at high AOA's and high cambers because they're small. With larger parts you would have no problems.

Also the wake structure in itself is the main problem since the diffuser and wing entertain their turbulence. You could keep the same levels and change the wake structure, the turbulence would decrease.

[wesley123]

fazit: the cars will look less appealing, the turbulence will still be relatively high and passing will still be difficult but a bit better.

That's pure speculation.

The wake structure will be similar, the strength of turbulence not.

After that, the question is to know if the teams will really make cars that follow the OWG lines. But you can't say anything before you see it.

On the plans, the turbulence will be drastically reduced.

But turbulence was never the only problem.

My Fluid dynamics knowledge is rather rusty, but isn't turbulence (downstream wake) the major contributor to drag? If turbulence is much reduced therefore drag will be too?

On another note: the diffuser for 2009 is much larger than I initially thought; no wonder the cars will only be 15% down on downforce.

Turbulence gets caused behind the wing, not on the start of it. Just take as example a cone and test it in cfd, the point will go straight through but behind it there will be turbulence. It can be reduced by letting the tips come together so the air flows good and doesnt get interrupted. Drag itself is the resistance that gets created when a car hits fluid(air), if you will take a square shape then there will be turbulence when it has hit, but with the nose it still does but not that much. The biggest turbulence generating parts are the suspension arms rear wing and wheels.

[Scotracer]

My Fluid dynamics knowledge is rather rusty, but isn't turbulence (downstream wake) the major contributor to drag? If turbulence is much reduced therefore drag will be too?

On another note: the diffuser for 2009 is much larger than I initially thought; no wonder the cars will only be 15% down on downforce.

Turbulence gets caused behind the wing, not on the start of it. Just take as example a cone and test it in cfd, the point will go straight through but behind it there will be turbulence. It can be reduced by letting the tips come together so the air flows good and doesnt get interrupted. Drag itself is the resistance that gets created when a car hits fluid(air), if you will take a square shape then there will be turbulence when it has hit, but with the nose it still does but not that much. The biggest turbulence generating parts are the suspension arms rear wing and wheels.

Yes, I just looked into my old notes from last year at uni and it's where the flow seperates from the object you get massive turbulance and that's where most of the drag occurs. I just expect with a more efficient front-wing, more efficient diffuser and smaller rear-wing we're going to see quite major reductions in drag.

One thing to note: I was looking at 1999 speed trap data and at Monza the Jordan hit 361km/h compared with 2007 (since it was dry) of 351km/h...and they had similar power. Just goes to show whilst we think we're going really rather fast, the regulations are certainly not efficient. Next year we may see 360km/h+ again

[Ogami musashi]

Turbulence gets caused behind the wing, not on the start of it.

Turbulence can happen anywhere from before a wing to the trailing edge.

In most nature's flows, the turbulence is present down to the boundary layer.
Laminar flows are really a special case of flow behavior.

Drag itself is the resistance that gets created when a car hits fluid(air)

No, drag is a pressure difference and/or a shear stress. in the case of impact on a nose cone, this is a pressure difference between the nose and the aft of the body that creates drag (this is form drag).

, if you will take a square shape then there will be turbulence when it has hit, but with the nose it still does but not that much. The biggest turbulence generating parts are the suspension arms rear wing and wheels.

In what interests us the biggest turbulence is not from arm suspensions or wheels.
It comes from the rear wing and diffuser coupling.



To make it clear, the losses of downforce experienced by the cars are almost dominated by upwash from the diffuser and turbulence from the rear wing that is energized by the diffuser.

That's why i said the wake structure is important.

[WhiteBlue]

that is by no means speculation. the problem of dirty air is directly related to downforce. it is proportional. you can argue about the benign effects of certain types of downforce elements but in the end more downforce means more dirty air.

That's totally false.

The strength of turbulence behind a car is not related to downforce but to design.
When you have one design, it is true the strength of the vortex increases with speed (and thus downforce) but the turbulence factor not.
You can have way more downforce without all the turbulence simple, replace a tiny high camber wing by a wide, large flatter or thicker one and you'll end up with far less turbulence.

With this you can add the importance of the wake structure.

And this is even more incorrect considering the detrimental effects on the following car are dependent on the sensitivity of the airfoils.

perhaps some cars have less drag and turbulence and have different turbulence patterns but that isn't going to overrule the efect of 1 ton more or less downforce. so with pretty good accuracy you can predict that a 15% reduction in downforce and some changes in the devices that produce the downforce you are not going to make the improvement in passing that a 50% planned reduction had brought. if you can defeat that logic tell me how.

That's not a logic, that's a statement.

You always have the example of the venturi channels that produces much more downforce without having any problems.

As i said, the problems with actual airfoils is that they are run at high AOA's and high cambers because they're small. With larger parts you would have no problems.

Also the wake structure in itself is the main problem since the diffuser and wing entertain their turbulence. You could keep the same levels and change the wake structure, the turbulence would decrease.

I'm not going to split hairs with you and I know you probably know more about aero than I do. But the design has certain natural limits and limits that are given by the traditional look of the car and the way the regulations are written.

I do not think that a very wide rear wing (say 3 m) would be practical. Also it will be difficult to limit designers to near flat low downforce profils.

Also the effect of diffusors on following cars is by far not so benign as you make believe when you listen to the explanation of the OWG.

Some years ago there was a fundamental investigation done in the UK which was government supportet. The main conclusion regarding aerodynamics was that limiting downforce would greatly reduce energy consumption and promote overtaking.

With a fixed downforce limit designers would automatically use 100% downforce and would focus all their efforts on reducing drag. That in turn would automatically promote overtaking because less drag means more benign wake structures and less dirty air for the following car.

I remember that Ciro posted that link and I recommend it for reading because it is fundamental. Perhaps he can find it again for us. I would appreciate your comments once you have read it. without that common ground the dispute appears useless to me.

[Jersey Tom]

McLaren's new design...



Well we can dream.

[Ogami musashi]

I remember that Ciro posted that link and I recommend it for reading because it is fundamental. Perhaps he can find it again for us. I would appreciate your comments once you have read it. without that common ground the dispute appears useless to me.

No problem, please let me know when you find it.

[boci]

Are wheel rims allowed for next year?

That Renault looked so good without them in parc-ferme.

[Scotracer]

Are wheel rims allowed for next year?

That Renault looked so good without them in parc-ferme.

That's what I thought watching the Renault and Kimi on the grid. Really nice.

[djos]

McLaren's new design...

Well we can dream.

I miss the 90's era Macca's & Willi's, they looked amazing!








and they were so low to the ground they created showers sparks during the day over small bumps!!! I'd almost forgotten how cool that looked until I saw the RBR's & Ferrari's bottoming out in Singapore last night.

[alex1015]

and they were so low to the ground they created showers sparks during the day over small bumps!!! I'd almost forgotten how cool that looked until I saw the RBR's & Ferrari's bottoming out in Singapore last night.

I believe the sparks in that era was because the Skid-planks were Titanium, now they are wood AFIAK. However, the sparks we saw in Singapore were from the Titanium blocks holding the skidplank in place.

OT: The flames from the exhaust were nice too see as well in Singapore

[Miguel]

Well, djos, that is the FW12 from 1988, although I bloody love the FW14B and the FW16. But...

OMG!!!! Jean-Louis Schlesser!! Twice!! Il Commendatore would be proud of you, the man responsible of the only non-McLaren win of the season, in the first race after Enzo passed away. If I were a McLaren fan, I'd be furious. But I'm not

BTW: I think old cars used to have a titanum skidblock instead of the wooden one they have today, so that explains the excess of sparks seen those days.

[djos]

Well, djos, that is the FW12 from 1988, although I bloody love the FW14B and the FW16. But...

Errrr yep good point, here are some FW14 pics.

BTW: I think old cars used to have a titanum skidblock instead of the wooden one they have today, so that explains the excess of sparks seen those days.

Yep, after Senna died (apparently tires lost too much heat & pressure causing car to completely bottom out and loose control) the FIA forced the teams to have a minimum ride height with a wooden plank - the plank is to measure wear and if it is measured to be worn past a certain point (a few mm IIRC) the team gets in trouble.