Innovo 2012 F1 Car - Tozza Mazza and JordanGP

[Tozza Mazza]

Wow that is very interesting to see, how did you manage to run CFD on that?

We sent the google sketchup (.skp) files to Godsire.
He converts the file into a format ( I can't remember which one, maybe .DXF?).
He then imports the file into solidworks and builds around the frame the .DXF file gives him. When done he has to delete this frame, which is a lot of effort.

Once this is done the part is ready for analysis, and can be moved into an assembly model for a larger analysis etc...

We have to do this process part by part, it's longwinded, but as you can see, it gets the results!

TM.

[Tozza Mazza]

Hi, quick update on the rear wing.

After the previous CFD we realised there were many problems with the wing.

The top element had hardly any pressure difference, so it wasn't creating much downforce, and the lower element was creating much less downforce closer to the endplate than in the centre of the wing.

To improve the wing, we made a few changes.

The angle of attack of the base wing was very low, so we decided to increase it to try and get the wing working better.

The gurney flap at the trailing edge of the upper element was removed, as it was causing a large amount of drag.

The centre of the upper element now has a triangle cut out in the centre, and the centre of the lower element now has a reduced angle of attack.

Finally, the width of the curved section was increased by 50%.

With DRS closed, the new wing gained 25% extra downforce, but also gained 25% extra drag.

However, with DRS open, we gained 83% downforce, but also gained 41% drag.

This wing has shown an obvious improvement to the previous rear wing, and hopefully in the next iteration we can reduce some of the drag that has been gained.

Hopefully I can get some pictures from this latest analysis up soon.

[N12ck]

wait a minute, with DRS open you gained downforce and gained drag?

DRS = drag reduction

i dont understand how you can gain downforce and drag with DRS,

[Tozza Mazza]

over the previous design, not over the DRS closed wing.

Both versions of the wing gave improved downforce, but more drag.

[Tozza Mazza]

Hi, quick update on the rear wing.

After the previous CFD we realised there were many problems with the wing.

The top element had hardly any pressure difference, so it wasn't creating much downforce, and the lower element was creating much less downforce closer to the endplate than in the centre of the wing.

To improve the wing, we made a few changes.

The angle of attack of the base wing was very low, so we decided to increase it to try and get the wing working better.

The gurney flap at the trailing edge of the upper element was removed, as it was causing a large amount of drag.

The centre of the upper element now has a triangle cut out in the centre, and the centre of the lower element now has a reduced angle of attack.

Finally, the width of the curved section was increased by 50%.

With DRS closed, the new wing gained 25% extra downforce, but also gained 25% extra drag.

However, with DRS open, we gained 83% downforce, but also gained 41% drag.

This wing has shown an obvious improvement to the previous rear wing, and hopefully in the next iteration we can reduce some of the drag that has been gained.

Hopefully I can get some pictures from this latest analysis up soon.

Okay,
Below are the CFD images. I will give a brief analysis.

OLD WING: Drag 266N, Downforce 900N
NEW WING: Drag 333N, Downforce 1129N








The Wing is now performing much better, well, under the wing at least anyway.
The problem we now have is that the air on top of the lower aerofoil is too fast, as there is a lack of high pressure in this area. This will probably need a change in aerofoil shape for the upper element of the wing, and I'm sure an increase of AoA on the flap to around 60 to 70 degrees may be wise.

The top element is still not performing as well as it could do.

[wesley123]

I would say the top wing is just lacking shape. What I see there just is just an cambered neutral airfoil. Might be possible to compare it a bit to other designs? For example I use way different wing profiles. And would be cool to compare both profiles to each other.

[ringo]

The pressure range is too high that's why you're seeing so much green.
Narrow the scale between 100000 Pa and 101900 Pa.
You make a better analysis of the underside that way.

[godsire]

Yes, I know. I did all these screens very fast using default/automatic scale. Now I adjusted it in a better way (101900 Pa was too low because highest pressure was about 101500 Pa). These are 2 screens showing the pressure distribution in both wings (new version and old version). The previous analysis shows that the flow under the wing is better in new version. Now we have a material for evaluation of flow above it:

[wesley123]

Why do you have an gurney on the inside of the end plates? It is supposed to be the other way, as this generates low ressure behind itself, the lower pressure in between the end plates, thus increases downforce.

BTW godsire, would you have time to do a CFD on my front wing for example? This part intrests me the most and I would like to see how it works. If not, could you give me an explaination how you set up the CFD and such so i can run my own?
thanks in advance

[godsire]

That is a small mistake during rebuilding. I will correct it and run analysis again.
Of course I can test your front wing (and maybe then compare results to our version) but maybe let's talk about it privately

[danfast66]

Does anyone know if there is a rule prohibiting the rear end plates from being completely gilled like they are at the bottom corners?

[ringo]

Yes, I know. I did all these screens very fast using default/automatic scale. Now I adjusted it in a better way (101900 Pa was too low because highest pressure was about 101500 Pa). These are 2 screens showing the pressure distribution in both wings (new version and old version). The previous analysis shows that the flow under the wing is better in new version. Now we have a material for evaluation of flow above it:

Try 101900. You don't really need to see the peak pressure. That will throw of the more critical low pressures. The peak pressure area is also in some arbitraty crevice on the wing, ussually the top side, which is not very sensitive.

Try 101900 Pa max and 100000 Pa min .. please..

[Tozza Mazza]

Try 101900. You don't really need to see the peak pressure. That will throw of the more critical low pressures. The peak pressure area is also in some arbitraty crevice on the wing, ussually the top side, which is not very sensitive.

Try 101900 Pa max and 100000 Pa min .. please..

Something interesting going on Ringo?!

[godlameroso]

Have you tried doing a CFD on a Williams style rear wing? I think the trick for the underside is not to just have a curved profile, but rather have it be like the front overhang/splitter of an LMP car.

[Tozza Mazza]

Have you tried doing a CFD on a Williams style rear wing? I think the trick for the underside is not to just have a curved profile, but rather have it be like the front overhang/splitter of an LMP car.

No we haven't yet, although that will come, just to see what it's doing!

Are you sure about that, don't LMP1 cars have a 'frontal diffuser' in that area, instead of a wing.

IIRC flow around the rear wing is fastest towards the endplates, so more Downforce can be generated there than in the centre, so in order to help flow at the centre of rear wing, you can reduce chord length of the main plane and decrease AoA, as airflow is very slow here (see Ringo's thread for some discussion on this).

EDIT: Man I love the 908