Wind Tunnel Vs CFD

[Smokey 6 litre]

Hi tech heads,

I am currently researching the sustainable benefits of CFD simulation against traditional wind tunnel testing as part of my Univertisty final year project, and was wondering if anyone knew of any journals or articles on the matter.

I am also looking for as many examples as possible, i am aware of the DBR9 which i believe was CFD designed and then track validated, and i think one of the new F1 teams is going down the same route but cant remember which. Any more examples or relevant articles/journals would be a great help to me.

Cheers.

[tristancliffe]

There was a small discussion on this topic a bit further down in the Racing Technology forum - http://tentenths.com/forum/showthread.php?t=118580

I don't know of specific journals that would help you, but the general feeling is that in both instances "poor data in = poor data out". Both have proven to be very effective, but also very wrong, even by talented people. Honda F1, for instance, couldn't have done much worse with a brick in 07/08, but the same people created the Brawn with much the same tools...

Purely CFD created F1 cars might be great, they might be rubbish. Only the stopwatch will tell.

[Smokey 6 litre]

Cheers,

I'm coming at this topic from a 'sustainability' angle which is horrible in itself because it has never been defined what sustainability actually is and nobody knows and every politician or marketing company uses it however they want.

I understand the complexity of the subject, the fact that CFD and wind tunnels are only simulation tools and the skill is in the use of those tools.

What i could really do with, assuming nobody can provide a link to some amazing article which i can plagarise the hell out of, is a good list of cars which were produced using CFD simulation and track validation only.

[Joaquin Topiso]

Originally Posted by Smokey 6 litre

Hi tech heads,


I am also looking for as many examples as possible, i am aware of the DBR9 which i believe was CFD designed and then track validated,

The DBR9 was designed using Southampton´s wind tunnel. Later, with the car already racing, they did the CFD for some minor developments.

The CFD company claims they did all the aero of the car, but the car was already done in the wind tunnel.

Originally Posted by Smokey 6 litre

and i think one of the new F1 teams is going down the same route but cant remember which.

Cheers.

I think that´s Manor.

[Smokey 6 litre]

Cheers for the Manor heads up, from what i've been reading seems like Nick Wirth is leading them down the CFD route he used for the LMP1 and LMP2 Acura's.

Accourding to my sources (Race Tech Magazine interview with George Howard-Chappell, Issue.61) the DBR9 was designed without a wind tunnel model, the basic shape was CFD computed and the full size car was tested at the MIRA facility and then validated with constant speed straight line test as cost down runs.
If there are any certifiable sources to contradict this i would be most interested in reviewing them.

Any more cars people can think of? Seems as though this part of the project is now focusing on the saving of expensive and wasteful manufacture of scale models, as well as the energy savings due to reduced wind tunnel running.

[Joaquin Topiso]

Originally Posted by Smokey 6 litre

Accourding to my sources (Race Tech Magazine interview with George Howard-Chappell, Issue.61) the DBR9 was designed without a wind tunnel model, the basic shape was CFD computed and the full size car was tested at the MIRA facility and then validated with constant speed straight line test as cost down runs.
If there are any certifiable sources to contradict this i would be most interested in reviewing them.

I guess George Howard-Chappell is linked to the consultancy company that did the CFD development. Later on, the car was tested on MIRA (no rolling ground full scale WT) and results didn't match. Then, with track data, CFD showed to be more accurate than the non-rolling ground WT testing (which is basically useless, IMHO)

I know someone on the Southampton WT who told me he worked on the DBR9 on the early stages. That's all I can say, as I cannot name a source. He could have lied to me. That WT is 40-50%, with rolling ground (about F1 standard nowadays).

Perhaps you can call to Southampton University to confirm this story.

[Smokey 6 litre]

I'll research that link, anything is useful at this stage.

[old man]

We have discussed this here for some time (see other thread) and my view at present is that a computerised design will give an excellent standard product but will it ever show ingenuity?

[MulsanneMike]

Originally Posted by Smokey 6 litre

Hi tech heads,

I am currently researching the sustainable benefits of CFD simulation against traditional wind tunnel testing as part of my Univertisty final year project, and was wondering if anyone knew of any journals or articles on the matter.

I am also looking for as many examples as possible, i am aware of the DBR9 which i believe was CFD designed and then track validated, and i think one of the new F1 teams is going down the same route but cant remember which. Any more examples or relevant articles/journals would be a great help to me.

Cheers.

Acura ARX-02A was essentially all CFD designed. I say essentially because Wirth Research did an initial 14 day tunnel program and then went to all CFD. The results are open to interpretation; in head to head competition with tunnel developed competition (Audi and Peugeot) the ARX-02a didn't do particularly well. But that could have been down to a number of unrelated issues (design concept in general). Acura ARX-01b ('08) developments was all CFD. As a long time model maker I still can't see the advantage of a CFD only route as long as budget isn't a particular issue. At the top level that will be the case and thus any serious outfit will complement a model program with CFD. Figure that in any given day I can bang out between 35 and 45 runs, each run through a 10+ point ride height map. And there are ways to keep model costs down, you have to be clever. Gone are the days of the $200,000+ model.

If you're interested in further discussion contact me via email.