Mercedes W09 Speculation Thread

[wesley123]

With the rules regarding weight(and I believe CoG as well), this isn't a very restricting factor in car design.

[mmred]

Everything is feasible, the only question is it worth it. For that design, you'd need to buff those arms up quite a bit. That adds weight. To the rear. A long way from the CoG. But, if aero is a lot better (just an example) then it could be useful and worth the trouble.

exactly
the problem is that it isnt even an aero advantage, cause keeping the aero interference far from the diffuser end makes the aero surface less useful not more useful to keep the diffuser flow attached

so i discussed the cynematic disadvantage cauuse the aero disadvantage is already certain

[mmred]

With the rules regarding weight(and I believe CoG as well), this isn't a very restricting factor in car design.

at the start of the season mercedes was supposedly 5kg overweight: adding some 2kg (?) of suspensions without a clear aero advantage ( see discussion above ) is a limiting factor

you cant simply use a front suspension solution on the rear, you have to rethink a better solution, there can be some, who knows...

do you remember this?



that one was a rear suspension with increased aero influence to the diffuser and the philosophy was really the opposite of this one, aero was kept as backwards as possible ...
but the cinematics were bad anyway and the aero advantage was not so big so it was discarded

[Vanja #66]

With the rules regarding weight(and I believe CoG as well), this isn't a very restricting factor in car design.

True. That's why I was thinking about polar moment of inertia, having heavy parts far from CoG isn't doing you any good on that front.

exactly
the problem is that it isnt even an aero advantage, cause keeping the aero interference far from the diffuser end makes the aero surface less useful not more useful to keep the diffuser flow attached

so i discussed the cynematic disadvantage cauuse the aero disadvantage is already certain

Are you sure about that?

[mmred]

With the rules regarding weight(and I believe CoG as well), this isn't a very restricting factor in car design.

True. That's why I was thinking about polar moment of inertia, having heavy parts far from CoG isn't doing you any good on that front.

exactly
the problem is that it isnt even an aero advantage, cause keeping the aero interference far from the diffuser end makes the aero surface less useful not more useful to keep the diffuser flow attached

so i discussed the cynematic disadvantage cauuse the aero disadvantage is already certain

Are you sure about that?

100% sure
moving the aero as close as possible to the rear diffuser is common standard, it is about impressing the highest possible upward deflection there without separation to allow the diffuser to not stall as well in the sudden expansion after the edge is reached, it s practically the whole purpouse of the monkeyseat combined with the exhaust
and the whole purpouse of the flaps at the diffuser edge as well

i am actually surprised you are uncertain about it

[Vanja #66]

Let's break that down a bit

moving the aero as close as possible to the rear diffuser is common standard

Not really, explained bellow.

it is about impressing the highest possible upward deflection there without separation to allow the diffuser to not stall as well in the sudden expansion after the edge is reached

Not really, but what you mention here is a solution to creating a low pressure zone above diffuser exit, to pump out the air underneath it. As rules don't allow teams to have another wing right above diffuser exit, they put them where they can - in front of it and in very aggressive positions.

it s practically the whole purpouse of the monkeyseat combined with the exhaust
and the whole purpouse of the flaps at the diffuser edge as well

Monkey seat is for the rear wing mainly, when you have extreme angles of attack of both wings on slower circuits, you don't want the flow to separate from the rear wing flap. Flaps around the diffuser edge are mentioned above.

On the contrary, arms that roon draw are moved forward and are (possibly) perpendicular to the airflow. This creates less disruption, as it allows for cleaner airflow above the diffuser. You want as clean as possible airflow above the diffuser, to have as much energy as possible to pump out the air under the floor. So it's a good thing in fact.

What McLaren tried a few years ago was (and still is) a mystery to me. Looking at it now (if it's an aero thing in the first place), I'm thinking they wanted to force a high pressure zone above the diffuser and at the same time leave those slots between them and between lower arms and diffuser. Trough those slots you'd have a high speed airflow with a nice amount of energy (much like slots between flaps and wings) to help pump out the air under the floor. The only problem is that those arms are moving in respect to diffuser and so you'd never have a constant height slot - you don't want that.

[mmred]

Let's break that down a bit

moving the aero as close as possible to the rear diffuser is common standard

Not really, explained bellow.

it is about impressing the highest possible upward deflection there without separation to allow the diffuser to not stall as well in the sudden expansion after the edge is reached

Not really, but what you mention here is a solution to creating a low pressure zone above diffuser exit, to pump out the air underneath it. As rules don't allow teams to have another wing right above diffuser exit, they put them where they can - in front of it and in very aggressive positions.

it s practically the whole purpouse of the monkeyseat combined with the exhaust
and the whole purpouse of the flaps at the diffuser edge as well

Monkey seat is for the rear wing mainly, when you have extreme angles of attack of both wings on slower circuits, you don't want the flow to separate from the rear wing flap. Flaps around the diffuser edge are mentioned above.

On the contrary, arms that roon draw are moved forward and are (possibly) perpendicular to the airflow. This creates less disruption, as it allows for cleaner airflow above the diffuser. You want as clean as possible airflow above the diffuser, to have as much energy as possible to pump out the air under the floor. So it's a good thing in fact.

What McLaren tried a few years ago was (and still is) a mystery to me. Looking at it now (if it's an aero thing in the first place), I'm thinking they wanted to force a high pressure zone above the diffuser and at the same time leave those slots between them and between lower arms and diffuser. Trough those slots you'd have a high speed airflow with a nice amount of energy (much like slots between flaps and wings) to help pump out the air under the floor. The only problem is that those arms are moving in respect to diffuser and so you'd never have a constant height slot - you don't want that.

the discussion is quite long

1) monkey seats interacts with the diffuser as well, it s litterary in the middle between diffuser and rear wing, while its upper flux creates high pressure that compensate for the bottom part of the wing low pressure thus allowing an higher ange of attack without stall, its bottom flux is low pressure and alleviates the high pressure over the diffuser ( top side ) thus reducing the disparity with the lower diffuser low pressure and high velocity and reducing the detachment and turbulent wake that comes from the sudden mix of two two much different fluxes, reducing stall ( that advances backwards into the diffuser ) and drag
i mean this is basic aerodinamic of profiles ( cfd eng here )
probably the interaction with the rear wing is more important, but i dont underestimate the interaction with the diffuser cause well the gearbox pilon there practically creates also an imminent separation there ( with its sudden end ) and lowering the pressure is a way to manage that separation over the diffuser too

2)but i agree that the flaps are the main example of air jets with low pressure pushed over the diffuser to raise the flux profile by profile without stall or detachment
of course the same works also for PUMPIN air out of the diffuser, but it s laminar air you want so you have to reduce the disparity in pressure between the two sides and lift up the flux, if you get separation you dont achieve the same deviation and drug increases and basically the diffuser is choked
pumpin and raisin up the flux is the same, i reason in terms of flow lines you reason in terms of pressure field ( it s a choice, i guess i am the weird one in this kind of reasoning but it s my habit to think about flow lines before pressure )
so i disagree with your "not really" : detachment is Exactly what you want to avoid

3)as u said too they cant put close profiles that s why mclaren did put its suspensions so backwards and that s the aero adv of suspensions, if done right ( the shape of the mclaren wasnt so intuitive tough, i guess they merely put a nolder shaped suspension that tried to detach the flow at the top side to reduce the pressure and improve the rear wing, and they had a more shape at the bottom side that interacted with the diffuser , they didnt use a conventional profile so the logic was different for the top )
so i disagree with the suspension seen just as detrimental aero interface
it s 10 years that suspensions are profiled. they are used exactly for that as an aero interface capable ( theoretically becuase with a neutral profile it s harder ) of lifting the flux

4) but also mclaren choice didnt prove effective that s why suspensions are mostly used as neutral surfaces that just prevent turbulence formation
so if puttin them closer to the front doesnt make no good, in my opinion, and in the general opinion of the teams till now, also putting it behind would require to use better profiles, but rules dont allow any profile to be used so the results are ineffective

4)the movement can either be a problem or an advantage, generally suspensions raise on turns where you need more load and the opening of the slot does have a positive effect, while you dont need too much load on the straight when they do lower down and the slot chokes, and the choking slot can make the diffuser under it stall or at least diverts the flux lines downwards reducing the effective aoa and so the overall diffuser load and drag

it could be good

i think mc failure was really more in the profile they could choose due to regulations, cause if you want something to act as a good aero device despite its pegiorative weight you want it more efficient and with a better profile

so far if there s no advantage in the backward suspensions position ( compared to weight increase ) my opinion is that the forward positioning ( with same weight increase and even less aero opportunity, cause a neutral suspension doesnt give the same advantage as one that trie to have an "active" aero ) is really useless, well detrimental to be honest

[atanatizante]

(Sorry if this topic was already discussed)
In order to improve halo`s airflow disruption towards engine air intake teams are allowed to put in place fairings and wings no more than 2mm thick, had I`m not wrong ...
My question is about being allowed to have a cascade wiglets structure acting for at least two reasons: one is to try to redirect the disrupted airflow but most of all to increase DF in a zone near the car`s CoG, hence the third benefit: to lower this one!

[godlameroso]

2 cm or 20 mm I was hoping for some miniature horns.

[dans79]

I bet someone will try dimples like a golf ball.

[Zynerji]

The question is about limits. I can see a fairing that wraps around the front part of the halo, but uses that as an anchor to sweep back 2 vertical wing pylons, and cantilever a beam wing where the shark fin was behind the engine cover.

[roon]

Continuing with the control-arm speculation: if longer arms benefit the tires by reducing lateral motion per a given wheel displacement, how far can this be taken? I imagine room can be made within the gearbox casing to draw the attachment points of the rear arms closer to vehicle centerline, in addition to mounting the upper arms above the gearbox, per the original speculation.

At the front, I say we extend each lower control arm to the opposite side of the chassis--a 'distal keel' setup, let's say. Ideally with symmetrical pivots but with asymmetrical arms to prevent clashing.

[roon]

The fitting mockup features halo attachment points, so it may be an accurate representation. I'm not sure if the roll hoop signifies they've dropped the large oval intake. Last year, was it bodywork over a small hoop, or was it all hoop?

[F1NAC]

This roll hoop looks like its 3d printed. Probably just there to measure head clearance

[PlatinumZealot]

Continuing with the control-arm speculation: if longer arms benefit the tires by reducing lateral motion per a given wheel displacement, how far can this be taken? I imagine room can be made within the gearbox casing to draw the attachment points of the rear arms closer to vehicle centerline, in addition to mounting the upper arms above the gearbox, per the original speculation.

At the front, I say we extend each lower control arm to the opposite side of the chassis--a 'distal keel' setup, let's say. Ideally with symmetrical pivots but with asymmetrical arms to prevent clashing.

https://i.imgur.com/ELXu9ZI.jpg

Like a monster truck?
Btw the setup you drew on the rear, I think Renault used that one year.