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A video of a CFD sim was posted in the F2012 thread. Obviously there's no moving wheels, no exhaust simulation, etc. But it's interesting nonetheless. Maybe some members who are more familiar with CFD can give their thoughts and how accurate the video may or may not be?

video from Erteclas --> http://vimeo.com/39096659

The CAD model may visually look something like a F2012, but is only an artist rendition of sorts. The exact geometry certainly did not come from Ferrari.

This CFD simulation dosnt take the exhaust gasses into account?

Otherwise i dont believe it would have that huge low preassure spot between the engine cover and the rear wing.

This CFD is definitely fan made. You can see his models in the other videos. Doesn't nearly have as many polygon meshes as I would expect from a top level team, doesn't even include the driver (which is vital to airflow around the crash protection structure. Is this a velocity or pressure distribution? I would guess pressure. Considering this is not a truly representative model, I would say that there is unusual behavior of the airflow on the engine cover from flow recirculating around the ACER duct (from the undercut). This would disrupt the laminar flow coming off the sidepod if this occurred in reality. I'd say there is likely a small bit of turbulent flow in this area from the real F2012 due to the truncation of the duct, but not nearly something like this with such strange recirculation behavior. The flow over the sidepod is affected due to the lack of the driver's body/helmet. Non spinning tires, especially the fronts, would totally change the pressure distribution of the flow as it reattaches near the sidepods. I would suspect that this is the reason for the unusual upwash effect around the ACER duct. The only good thing I can tell from this CFD is that the front and rear wing are mostly showing correct results.

No air hits the rear wing? No driver helmet? No air entering into brake ducts? Defiantly fan made unless air only exists across the bottom half of a race car

Inaccurate. There is something weird going on around the acer ducts. Almost like there is no air exiting them and that is causing air to flow towards the front of the car.

let's end this. It's a home brewed facsimile of a F2012. Totally worthless for any understanding of F2012

Can it be used for general car flow information:

1) Is it of value for evaluating flow around the radiator inlet, barge board? An amazing amount of flow is channeled out side of the rear wheels. I would have thought that the coke bottle side pods would have allowed more of this flow inside towards the rear wing.

2) Did you watch the stepped nose video? That seem accurate in shape and configuration. The flow goes all to hell very rapidly after hitting the ramp.

Lets face it, this is the best general current F1 design CFD we have.

Brian

hardingfv32 wrote:Can it be used for general car flow information:

1) Is it of value for evaluating flow around the radiator inlet, barge board? An amazing amount of flow is channeled out side of the rear wheels. I would have thought that the coke bottle side pods would have allowed more of this flow inside towards the rear wing.

2) Did you watch the stepped nose video? That seem accurate in shape and configuration. The flow goes all to hell very rapidly after hitting the ramp.

Lets face it, this is the best general current F1 design CFD we have.

Brian

Maybe for very vague impressions, but F1 has to be accurate to whatever minute scale it is they work on. So this thing can't be anywhere near that refined unless Ferrari kicked down their CAD files to some random guy. Also there are no spinning tires, no exhaust etc. so it might not even be good enough for vague impressions.

Pierce89 wrote: Also there are no spinning tires

I noted that in your earlier statements. What is the standard practice in such simulations? Why do you assume the wheels are not spinning? The program code could account for spinning wheels.

Brian

Just look at the flow at the sides and above the wheels. Totally undisturbed.

hardingfv32 wrote:

Pierce89 wrote: Also there are no spinning tires

I noted that in your earlier statements. What is the standard practice in such simulations? Why do you assume the wheels are not spinning? The program code could account for spinning wheels.

Brian

If the spinning of wheels is accounted for in the code, then he needs to work on his post processing because those flow lines aren't behaving like they're hitting spinning wheels.

For those that don't know post processing is converting the numbers spit out by CFD etc. and turning them into "colorful pictures"

hollus wrote:Just look at the flow at the sides and above the wheels. Totally undisturbed.

Do you see a lot of difference? Are these small differences going to be visible??

This is from: CFD Analysis of Air Flow within a Front Wheel Cavity by Carlos Arranz de Blas

PM me with your Email for a PDF of the article.




By hardingfv32 at 2012-03-25

even if the wheel is spinning, which I doubt, it still doesn't account for the exhausts, which do have a non-negligible effect.

Lycoming wrote:even if the wheel is spinning, which I doubt, it still doesn't account for the exhausts, which do have a non-negligible effect.

So you see a big difference in the flow of the illustrations above?

I can live without the exhaust. Do the research, this is as good as you are going to find on the current cars.

Brian