Red Bull RB9 Renault

[ajdavison2]

Wow I haven't sene any other teams use that many strakes under the front wing, I've seen 2 or 3 but never 5 on each side. Are they effectively turning (or trying to anyway) the front wing basically into a diffuser?

[Owen.C93]

But you correlate a modified experiment ,don´t you?

and

good luck ,I don´t buy it.It´s useless crap to me ,as is the flowwiz voodoo (where is the sense of applying a liquid to a surface and then go around a circuit at x speeds ,x-acceölerations and completly unpredictable influences ? I never saw any team actually video capturing their flowviz runs on track which would make it all a lot more worthwhile doing

That's exactly what I was wondering also (referring to both - the pitot arrays and the flow viz).

That massive grid will have significant effects upstream and will yet only measure individual (read fluctuating) data in a turbulent flow. So two effects that make me both wonder what you can really read from the results.

And for the flow- viz: For what speed do you want to determine the actual flow? I'm pretty sure that the local speed and direction in an area passed by a rotating vortex will change so much that at the end of one lap you only have a big mixture of traces. It might work if you want to identify if flow separation occurs under any circumstance at a given location but beyond that? I don't see how you could correlate certain elements of a flowviz trace with a certain speed or behaviour of the car in a certain condition !?

You test separation and also just make sure it matches what it did when you put it on the wind tunnel model.

[shelly]

And for the flow- viz: For what speed do you want to determine the actual flow? I'm pretty sure that the local speed and direction in an area passed by a rotating vortex will change so much that at the end of one lap you only have a big mixture of traces. It might work if you want to identify if flow separation occurs under any circumstance at a given location but beyond that? I don't see how you could correlate certain elements of a flowviz trace with a certain speed or behaviour of the car in a certain condition !?

Teams rely on the fact that the flow vis do not have a strong dependance on speed - they do depend on car's attitude (yaw especially. Any way you can always correlate the pictures with the vehicle dynamics data of the run and check for ranges (e.g. you see that you had yaw form -5° to 5° during the lap, you expect to see the swept pattern of the vortex being in between where you predicted it to be at -5 and at +5)
I agree about detecting speartaion with owen: you never want ot see detached patterns on the car at condition (drs or drd excluded) so you use paint to check that - for example the loss of boundary layer energy and late separation along the sidepod is crucial from 2012 because of coanda exhaust. This is very difficult to check in the wt, because the Reynolds number is not the same (lower Re in the wt could in same cases lead you to go too conservative); cfd is erratic in predicting spearation (could anticpate or delay it compared to real, depending on the turbulence model for example) so flow vis is really your tool for separation

[H2H]

Tyre Squirt Slot added to the RB9 (Not sure if it's on both cars yet)

https://pbs.twimg.com/media/BJ_gf6wCUAAYWMk.jpg:large

Nice catch, lots of ressources and finetuning going into that area.

Overall I get the feeling that tyre management on Sunday has indeed become the focal point of the setup. With different tyre strategies and all the resulting consequences it is key to be able to push consistently during the race.

[henra]

Teams rely on the fact that the flow vis do not have a strong dependance on speed - they do depend on car's attitude (yaw especially. Any way you can always correlate the pictures with the vehicle dynamics data of the run and check for ranges (e.g. you see that you had yaw form -5° to 5° during the lap, you expect to see the swept pattern of the vortex being in between where you predicted it to be at -5 and at +5)

I would expect some speed dependency in areas where vortices are present. The existance, angle, diameter and postion of these vortices will ususally change with the speed. And that is where I would exect severe difficulties in correlating traces with the situation at a certain speed or track position

I agree about detecting speartaion with owen: you never want ot see detached patterns on the car at condition (drs or drd excluded) so you use paint to check that - for example the loss of boundary layer energy and late separation along the sidepod is crucial from 2012 because of coanda exhaust.

and:

You test separation and also just make sure it matches what it did when you put it on the wind tunnel model.

OK, Agreed, that makes sense.

[shelly]

This picture posted by Stefan above it's interesting because the orientation of the probes gives us a hint about the expected direction of the flow on the rake grid, as the probes should be more or less aligned with the flow to minimize interference. It is notoceable the difference betwwen the steep angle behind the beam wing and the less aggressive angle outside the endplate - tha transition between these two angles is where the endplate extensions work. Notice also the gradual increase bottom to top form diffuser to back of beam wing- this is where the "floor gurney" (that has now become a multi element flap) works

[flyboy2160]

I also disagree completely with the claims that the rake and the Flow Vis tests are useless.

The Flow Vis is used, as already stated above, to verify what you've already seen either in CFD on in a tunnel.

It wouldn't surprise me to learn that teams have CFD runs with and without the rakes to see what effects they might cause before they track test. (I've done this with wind tunnel model mounts.)

[Mr.G]

https://imageshack.us/scaled/large/713/redb1h.jpg
https://imageshack.us/scaled/large/189/redb2.jpg

Did they get rid of the resonating chamber on exhaust?

[Owen.C93]

https://imageshack.us/scaled/large/713/redb1h.jpg
https://imageshack.us/scaled/large/189/redb2.jpg

Did they get rid of the resonating chamber on exhaust?

It's between the engine and exhaust.

[stefan_]

Spain 2013 - Sunday (12.05.2013)

[Crucial_Xtreme]

Gary Anderson's take on the new/er RB9 FW used in Barcelona


via AutoSport

[zac510]

RBR must have hired some Gillette engineers (just keep adding more blades!)

[variante]

RBR must have hired some Gillette engineers (just keep adding more blades!)

yes indeed...seven elements is a lot. But Red Bull's engineers (and Ferrari's) can't go much further: increasing the number of overlapping wings means to reduce the gaps in between them, which leads to a greater boundary layer prominence over "clean" air...very bad if you want to keep the airflow to stay adherent to the wing. It also causes a slight loss of high pressure on top of the wing.

[SiLo]

Like Ferrari though, they always run with the maximum AoA in their front wings, meaning they would be bleeding off pressure and the possibility of stalling by adding more elements, meaning they can then add more slots.... Circular development?

[Neno]

For a sake of new -1 on my reputation i agree with all previous posts. Adding new 2 elements on front wings means they running in dead end with devolopment, because you cannot find anymore aero performances, so you trying to have constant downforce and with many small slots trying to get from best optimal package to use. It's called refining already existing package. Renault 2006 already did that, trying to refine already optimum package with many small parts, wings slots on existing package to get what they already have on best optimum lvl.

When you see team who constantly bringing updates as completly new front wing, floor, or diffirent type of rear wing solution then you can see this car have space devolopment to make constant progress in bringing more downforce. But when you see like Red Bull just refine's on package it means there is no more room for something new as only to optimise what they already have.