Beam Wing Flo-Vis Results

[Crucial_Xtreme]

This is from the Sauber today in Mugello. See flow pattern by endplates. I assume stall? What would cause this? Separation? Shelly? Any of the other aero experts want to chime in?

[hardingfv32]

Does the beam wing need to be a uniform shape? Is this AoA a compromise ?

Maybe some of the exhaust routing is about getting uniform flow over the width of the beam wing.

Brian

[jordangp]

Another point to mention , that's a bit OT, is there are 2 perforations in the diffuser along the centre? I thought you were only allowed one.

[marcush.]

Can anybody explain why they do not :

have cameras mounted to the car to record how the paint patterns develop over time so you can analyse the separation phenomenons as they develop -and maybe see why it happens?

Why donb´t they use smoke wands to visualize the air moving over the car? flow fiz seems to tell only about boundary layer issues..but is the general flow of no importance?

[wesley123]

Another point to mention , that's a bit OT, is there are 2 perforations in the diffuser along the centre? I thought you were only allowed one.

It's one hole, take a hood look in the center, you'll see the broken up surface there connecting the two holes.

As for the beam wing I would say stall too. This stall seems to be caused by these two white things on the underside of the wing, looking from there you'll notice different flow. This together with the effec tthe end palte has probably causes the wing to stall. Lots of teams reduce AoA to the tips of the beam wing to reduce vortices and possibly also the effect happening here

[Lycoming]

Why donb´t they use smoke wands to visualize the air moving over the car? flow fiz seems to tell only about boundary layer issues..but is the general flow of no importance?

If you want to do this outside of the wind tunnel, the car would have to carry smoke.

[marcush.]

Why donb´t they use smoke wands to visualize the air moving over the car? flow fiz seems to tell only about boundary layer issues..but is the general flow of no importance?

If you want to do this outside of the wind tunnel, the car would have to carry smoke.

if you put a rake in aero sensitive areas you modify the area you try to measure....

I´d prefer to carry a smoke generator...for testing purposes...

[Robbobnob]

Does anybody have any shots of the Sauber beam wing during preseason tests?

What if by opting for the Mclaren exhaust solution they are sacrificing the flow quality to the beam wing, arriving more turbulent and therefore separating. In their CFD analysis they could have identified a flow separation problem and opted to flow-vis to correlate their results, before designing a new beam wing with 1 degree less AOA.

totally speculation, but just a curious thought that i had.

[matt090290]

I know Sauber have stated the will not pursue a mercedes style DDRS but is it possible they've gone a different route with it and decided to try and stall the Beam wing?? this would require much less ducting as it would only have to travel down the rear wing endplate and may provide some decent returns... What do you all think?

[hardingfv32]

It would have been done the day after the protest was settle IF it actually helped. This would be a very easy project.

Brian

[flynfrog]

Why donb´t they use smoke wands to visualize the air moving over the car? flow fiz seems to tell only about boundary layer issues..but is the general flow of no importance?

If you want to do this outside of the wind tunnel, the car would have to carry smoke.

if you put a rake in aero sensitive areas you modify the area you try to measure....

I´d prefer to carry a smoke generator...for testing purposes...

a smoke generator is good at giving you pretty pictures not so good at hard numbers that is what the teams need.

[hardingfv32]

In an A380 video they show a model being catapulted through a wall of smoke to visualize the wing vortices. Is this a common technique in aerospace?

Brian

[flynfrog]

In an A380 video they show a model being catapulted through a wall of smoke to visualize the wing vortices. Is this a common technique in aerospace?

Brian

most data from a wind tunnel or flight test will come from instrumentation. sometimes tuft testing or smoke testing is used generally to get a visual idea of what is going on or when your aero group is completely lost and the data doesn't make sense then a tuft test is used. The problem with using tuft tests is that you need a camera up close and personal to the test article. IE you need a chase plane.

[strad]

Smoke is fine in an enclosed space like a wind tunnel but not so much out where crosswind and other factors can mess with your smoke.