Red Bull RB15

[lio007]

Is the air sucked into the area below the Siemens-logo?
For me the flow pattern points upwards from the floor. But to be honest I absolutely don't know if that would make any sense.

It makes perfect sense if you're trying to aim a vortex in between the engine cover and rear wheel, particularly if you're using the undercut of the engine cover to do so.

The air under the car will always be faster than the air above it because the air below is squeezed into a smaller volume due to the road and floor being so close to each other.

If you look closely these cars already have the ground effect tunnels that they plan for 2021, they use the bargeboards to form vortecies to create the outer wall of the "tunnel" since the floor is flat, the vortecies keep the air from spilling out from under the floor. Ironically you have to spill some air from the side of the floor to create the vortecies which fence in the airflow going underneath the car. If you spill too much air trying to seal the floor you don't get enough flow in the actual floor itself. Conversely if you don't spill enough air to create a consistent vortex along the floor, it spills out of the floor under yaw and you get horrible downforce instabilities.

So one needs to find a right compromise of floor sealing vortecies created by the bargeboards, while allowing and directing enough mass air flow to keep the diffuser sucking.

The RB15 has been fine tuning this compromise since the season started and have started making serious gains because of this. I'm just glad the chassis has enough flexibility to allow development.

I still think those wastegate pipes have something to do with it, because the car's performance has increased with the timing of those pipe modifications.

Thank you for your explanations.
This is the reason why F1 sometimes drive me crazy...hell, they are doing "just" minor changes, but every weekend.
A little bit of FW-endplate update here, some extension of nose turning vanes there and so on.
RBR as we are familiar with, constant development instead of big updates during the season.

[godlameroso]

Is the air sucked into the area below the Siemens-logo?
For me the flow pattern points upwards from the floor. But to be honest I absolutely don't know if that would make any sense.

It makes perfect sense if you're trying to aim a vortex in between the engine cover and rear wheel, particularly if you're using the undercut of the engine cover to do so.

The air under the car will always be faster than the air above it because the air below is squeezed into a smaller volume due to the road and floor being so close to each other.

If you look closely these cars already have the ground effect tunnels that they plan for 2021, they use the bargeboards to form vortecies to create the outer wall of the "tunnel" since the floor is flat, the vortecies keep the air from spilling out from under the floor. Ironically you have to spill some air from the side of the floor to create the vortecies which fence in the airflow going underneath the car. If you spill too much air trying to seal the floor you don't get enough flow in the actual floor itself. Conversely if you don't spill enough air to create a consistent vortex along the floor, it spills out of the floor under yaw and you get horrible downforce instabilities.

So one needs to find a right compromise of floor sealing vortecies created by the bargeboards, while allowing and directing enough mass air flow to keep the diffuser sucking.

The RB15 has been fine tuning this compromise since the season started and have started making serious gains because of this. I'm just glad the chassis has enough flexibility to allow development.

I still think those wastegate pipes have something to do with it, because the car's performance has increased with the timing of those pipe modifications.

Thank you for your explanations.
This is the reason why F1 sometimes drive me crazy...hell, they are doing "just" minor changes, but every weekend.
A little bit of FW-endplate update here, some extension of nose turning vanes there and so on.
RBR as we are familiar with, constant development instead of big updates during the season.

Those tiny changes are to get that balance between the air mass and sealing vortices. Having thought about it more, the heat from the wastegate pipes has a very predictable effect on any flowing air mass. Heat creates increase in air volume, so naturally air would have a tendency to expand in volume as it does for example in a turbocharger. What happens to a vortex when a heat source is introduced?



This is obviously an extreme example



But in principle it works similarly because the air flow and the exhaust are semi-controlled variables.

I suppose next year this little loophole will try to be closed, however you cannot unlearn what you have learned. Like getting shocked for the first time it stays with you.

[roon]

Maybe they are switching/balancing flow left-to-right out of the wastegate pipes. On a right-hander, flow could be increased out of the right WG pipe, to increase air mass & velocity under that side of the wing which would be in the shadow of the endplate.

[godlameroso]

Maybe they are switching/balancing flow left-to-right out of the wastegate pipes. On a right-hander, flow could be increased out of the right WG pipe, to increase air mass & velocity under that side of the wing which would be in the shadow of the endplate.

https://maxf1.net/wp-content/uploads/20 ... d-Bull.jpg

https://pbs.twimg.com/media/D_cizn2WkAIzgCV.jpg

Makes sense when you consider the design working in yaw. A way to add more downforce on the unloaded side? Looks like Red Bull have a more elegant and more effective use of the end plate retraction as an aero surface than say, Reno.

[roon]

Makes sense when you consider the design working in yaw. A way to add more downforce on the unloaded side?

Was one way to explain the outward splay. Havent seen that before. It could be that its merely the most neutral place for them, or simply they block the engine cover outflow less. Also, should note they terminate under the middle of the RW so they cant really point directly at it. Some more views of them:

[godlameroso]

Not needed to interact with rear wing, just the vortex formed behind the car. Aero at the rear of the car influences front aero as well because, well air is always full of itself and will always show it's face. If you squeeze a balloon in one place the other side gets fat, that sort of thing.



Honda's whirligig wastegate exhausts, plus RB's aero genius = massive boost to upwash and in turn more under car airflow due to heating. And there's effectively no way of policing this save removing exhausts from cars.


This picture shows that there are 2 counter rotating vortecies being expelled from the diffuser and upwashing. The exhaust heats these vortecies, and as shown by introducing heat a vortex can feed on itself, and the vortex itself increases the radiation of the heat source.

If you get the exhaust to interact with that vortex, it's the equivalent of timing a well placed push on a swing.

And maybe it's not just an aero benefit but also an exhaust heat benefit, which could mean better regeneration from the MGU-H.

[Maplesoup]

Not needed to interact with rear wing, just the vortex formed behind the car. Aero at the rear of the car influences front aero as well because, well air is always full of itself and will always show it's face. If you squeeze a balloon in one place the other side gets fat, that sort of thing.

Yes, but no in so many ways. Air inside a sealed container does not behave the same as air moving round an F1 car going 300kmph

[godlameroso]

Not needed to interact with rear wing, just the vortex formed behind the car. Aero at the rear of the car influences front aero as well because, well air is always full of itself and will always show it's face. If you squeeze a balloon in one place the other side gets fat, that sort of thing.

Yes, but no in so many ways. Air inside a sealed container does not behave the same as air moving round an F1 car going 300kmph

Air moves through an F1 car as well, not just through the body to cool heat exchangers, but to power the engine as well. There are several controlled vortecies formed around the body which behave as containers do they not? I mean in the sense of guiding or constraining airflow.

If you increase the rate of upwash, you increase the speed of air traveling under the car to compensate which creates even lower pressure from the front of the car on back.

[Maplesoup]

Not needed to interact with rear wing, just the vortex formed behind the car. Aero at the rear of the car influences front aero as well because, well air is always full of itself and will always show it's face. If you squeeze a balloon in one place the other side gets fat, that sort of thing.

Yes, but no in so many ways. Air inside a sealed container does not behave the same as air moving round an F1 car going 300kmph

Air moves through an F1 car as well, not just through the body to cool heat exchangers, but to power the engine as well. There are several controlled vortecies formed around the body which behave as containers do they not? I mean in the sense of guiding or constraining airflow.

Right!!! I get you. You mean the through body aero for the radiators etc etc. Yea the front of the car is used to direct air either into or around the sidepods.

Teams always aim to have a certain air intake to outlet ratio. Which is effected by quite a few things like heat and speed of the air moving through the body.

Having a smaller outlet than inlet will cause drag to a degree but not so much so that the movement of air would affect the front wing.

[roon]

Not needed to interact with rear wing, just the vortex formed behind the car. Aero at the rear of the car influences front aero as well...

Interacting with the downstream flow, at points distant from the aero devices, probably makes the effects marginal. Compare to EBD which located the exhaust right next to the diffuser vortex.

This picture shows that there are 2 counter rotating vortecies being expelled from the diffuser and upwashing. The exhaust heats these vortecies, and as shown by introducing heat a vortex can feed on itself, and the vortex itself increases the radiation of the heat source.

Would need to add energy to increase temp within the vortex. The fire vortex increases temp because it is burning fuel more efficiently. The wastegate exhaust has no fuel nor is it combusting.

All teams interacting with the wake via exhaust, inevitably. Merc point their WG pipes at the crash structure winglets, for example. It's hard to say if RB are interacting with diffuser vortices or RW vortices, if either, but they may be.

[Morteza]

They have brought back the chimney (via @AlbertFabrega)

[Pyrone89]

Seeing pretty normal temps are expected it does seem they are after an aero benefit as opposed to being forced to do it because of cooling.

[Morteza]

Some nice shots from AMuS

[Pyrone89]

Car looking very on edge and a handful at the moment.

[IvailoStefanovBG]

Car looking very on edge and a handful at the moment.

I think this sensitiveness will disappear with temperatures rising in the afternoon...