Williams FW43B

[Just_a_fan]

How do they get the three fins / VGs in below the diffuser? Doesn't the surface facing downwards have to be visible from below? I.e. the diffuser's surface must be visible and those fins would prevent that.

Those are the footplate - it's a weird quirk in the software because the mesh isn't watertight it shows parts which aren't on the slice plane as if they're on the same plane.

Footplate? How do any fins get formed below the car? The surfaces are supposed to be continuous aren't they?

[jjn9128]

Footplate? How do any fins get formed below the car? The surfaces are supposed to be continuous aren't they?

They're not below the surface, they're outboard of the diffuser.

[Just_a_fan]

Footplate? How do any fins get formed below the car? The surfaces are supposed to be continuous aren't they?

They're not below the surface, they're outboard of the diffuser.
https://db3pap006files.storage.live.com ... pmode=none

Ah! I understand now. D'oh! from me there

[wesley123]

Such design was already done around 2000, afaik the Jordans had a very similar kick

Yes. I'm surprised they've "lengthened" the diffuser so much though.

I guess it's this rule:

The surfaces lying on the step plane which do not meet one of the vertical transitions may be curved upwards at their boundaries with an arc whose radius of curvature is no greater than 100mm at any point, with no inflection, which is tangential to the surface and applied perpendicular to the boundary. In no case may the arc start further than 100mm from the boundary (when measured on the surface and perpendicular to this boundary).

If I remember correctly such a design was done to deal with the boundary layer. Sadly enough can't find where I got it from

[jjn9128]

Such design was already done around 2000, afaik the Jordans had a very similar kick

Yes. I'm surprised they've "lengthened" the diffuser so much though.

I guess it's this rule:

The surfaces lying on the step plane which do not meet one of the vertical transitions may be curved upwards at their boundaries with an arc whose radius of curvature is no greater than 100mm at any point, with no inflection, which is tangential to the surface and applied perpendicular to the boundary. In no case may the arc start further than 100mm from the boundary (when measured on the surface and perpendicular to this boundary).

If I remember correctly such a design was done to deal with the boundary layer. Sadly enough can't find where I got it from

Makes some sense. Basically they force turbulent transition for all Reynolds numbers at that point. Means at higher Reynolds numbers the diffuser might separate and stall - might be advantageous. It means the diffuser kick is <100mm more upstream than the “diffuser” too. So bit more forward COP.

[Manoah2u]

Got to get some races under their belt, but it does seem the Williams is performing rather decent.
Will be interesting for some smart people to take the leaked car model and investigate it profoundly,
and compare it to their 2020 contender and where they have changed things.

Offcourse there's more than just aero, but with their own high-res models out there, and to compare this to race data, i'm sure there's some stuff to learn. If I were HAAS and AlfaRomeo, i'd get my hands on some student of aerodynamics to do a unpaid internship with some benefits (visit races and talk to the engineers) and use it to learn some stuff. With some luck you learn something you might not know or understand Williams' aero phylisophy and why it works/didnt work.

[variante]

Unfortunately I think it's too dirty to do any CFD with

Akhchuallyi...

Not the best CFD in the world, but this is about as much as my laptop can handle.
When i first saw that weird step, i thought "WTF is that?". Wesley mentioned an old Jordan using an apparently similar geometry for aero purposes, which also came to my mind, but this is essentially different, and probably serves no aero purpose. Your explanation, that this is to "cheat" the regulations, makes sense and really explains this oddity.
Pretty smart trick, i must say.

If I were HAAS and AlfaRomeo, i'd get my hands on some student of aerodynamics to do a unpaid internship with some benefits (visit races and talk to the engineers) and use it to learn some stuff.

I guess i should unmute my phone for THE call.
Hopefully, it won't be from Williams suing me for espionage...

[jjn9128]

Unfortunately I think it's too dirty to do any CFD with

Akhchuallyi...
https://i.imgur.com/x610kHs.png
Not the best CFD in the world, but this is about as much as my laptop can handle.
When i first saw that weird step, i thought "WTF is that?". Wesley mentioned an old Jordan using an apparently similar geometry for aero purposes, which also came to my mind, but this is essentially different, and probably serves no aero purpose. Your explanation, that this is to "cheat" the regulations, makes sense and really explains this oddity.
Pretty smart trick, i must say.

This is the CAD model, or did you recreate it?

[variante]

This is the CAD model, or did you recreate it?

The actual thing, in all its glory.
I had to work on it a bit, and there is no internal aero. But it gives an idea...
(I've also added a copy of the old strakes, from 2020)

[jjn9128]

This is the CAD model, or did you recreate it?

The actual thing, in all its glory.
I had to work on it a bit, and there is no internal aero. But it gives an idea...
(I've also added a copy of the old strakes, from 2020)

Well that needs a front page article

[Manoah2u]

This is the CAD model, or did you recreate it?

The actual thing, in all its glory.
I had to work on it a bit, and there is no internal aero. But it gives an idea...
(I've also added a copy of the old strakes, from 2020)

absolutely boss

[Stu]

Unfortunately I think it's too dirty to do any CFD with

Akhchuallyi...
https://i.imgur.com/x610kHs.png
Not the best CFD in the world, but this is about as much as my laptop can handle.
When i first saw that weird step, i thought "WTF is that?". Wesley mentioned an old Jordan using an apparently similar geometry for aero purposes, which also came to my mind, but this is essentially different, and probably serves no aero purpose. Your explanation, that this is to "cheat" the regulations, makes sense and really explains this oddity.
Pretty smart trick, i must say.


That is great!
The ‘trip’ edge formed at the edge of the radius and diffuser roof section doesn’t appear to be doing much, which makes it a bit strange (IMO); what effect would it have if the surface on the rear face were porous and connected to the rear of the diffuser (by a hollow section diffuser ceiling). Just curious....

[Mattchu]

So it would seem Williams are the only team on the grid that still uses mostly sloted horizontal louvres in the barge-board area!

I wonder if we`ll see that changed during the course of the season or they don`t see much gain and will concentrate on next year...

I thought this was a nice shot, but shows how much girth the FW43B has.

[DP_CFD]

This is the CAD model, or did you recreate it?

The actual thing, in all its glory.
I had to work on it a bit, and there is no internal aero. But it gives an idea...
(I've also added a copy of the old strakes, from 2020)

Do you have a link to the old 2020 strakes, or is that something personal of yours? I'm around here so I don't really know my way around the forum.

[variante]

Do you have a link to the old 2020 strakes, or is that something personal of yours? I'm around here so I don't really know my way around the forum.

Better if you model them by yourself, because i can't ensure their accuracy.
They're quite easy to make...just a couple of vertical extrusions.