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Farnborough
Farnborough
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Re: Mercedes W14

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AR3-GP wrote:
07 Apr 2023, 22:16
vorticism wrote:
07 Apr 2023, 22:12

I'll maintain it might also be worth considering that it's relatively aero neutral.
If it was aero neutral, it wouldn't shed a vortex. Or rather, a pretty inconsequential one which is the opposite of what Merc had in mind. That thing is clearly downwashing air. You can't say it's neutral.
Yes, astute observation there.

My view is to stick a gurney on top trailing edge (already said in above post) to alter it's performance in vertical to see what it does. Cheap and instant track test :D it would tell them something.

May be good, bad diabolical or switches on neutrality, they'd certainly see something.

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ringo
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Re: Mercedes W14

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The mid wing may be aero neutral or it may generate lift. I suspect if the upstream air of it is not coming to it straight, it can possibly be neutral or by a stretch generate downforce. The air is not hitting it head on like clean virgin air without any 3d considerations. The air is rolling through the control arms, and from over the top of the chassis, then there is the upwash from the front wing.
The net force from the wing depends heavily on the angle of attack, and that is relative to the localized flow vector upstream.
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AR3-GP
AR3-GP
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Re: Mercedes W14

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It is minimum a form drag generator because it has a cross section. Furthermore, look at the top of the side pod, the floor leading edge, and everything around the midwing. It's downwashing. This is not rocket science. This is even corroborated by Kyle Engineers (the former Merc aero), and the Vanja/Shub CFD collaboration projects.
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AR3-GP
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Re: Mercedes W14

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ringo wrote:
08 Apr 2023, 04:30
The mid wing may be aero neutral or it may generate lift. I suspect if the upstream air of it is not coming to it straight, it can possibly be neutral or by a stretch generate downforce. The air is not hitting it head on like clean virgin air without any 3d considerations. The air is rolling through the control arms, and from over the top of the chassis, then there is the upwash from the front wing.
The net force from the wing depends heavily on the angle of attack, and that is relative to the localized flow vector upstream.
https://cdn.crash.net/styles/large_arti ... 9.0064.jpg
There is no phantom downwash that is occuring ahead of the mid-wing, causing it to generate downforce. Come on, stop it.
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PlatinumZealot
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Re: Mercedes W14

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Farnborough wrote:
07 Apr 2023, 20:20
"You say I can't look at sidepods in isolation and then do exactly that with the mid wing #-o"

I've said no such thing, and not here to tell anyone else what to think.

I do think valid discussion does bring interesting thoughts into public though.

The mid wing has an upper and lower surface that exist in isolation (thats one unit of a complete wing form) that's in contrast to all the other competitors. It does resolve it's flow as a wing giving lift, no matter what you say about it.

They can't, or haven't yet, given any public airing of changing that so far, they still haven't solved their stated problem of not enough downforce with the iteration they've brought to the races this year.
You got this one wrong here my friend. In Race car aerodynamics you cannot take aero-surfaces in isolation, you must look at the relative flow around this mid-wing. The angle of flow approaching this mid-wing is extremely important.

Side pods inherently make lift by their shape. It's a big challenge to reduce or negate this lift. The Mercedes mid wing and the zero-pod that follows it can only be compared if one has the necessary tools. You just can eye-ball it and says it makes more lift than a normal side pod or water slide side pod.
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PlatinumZealot
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Re: Mercedes W14

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AR3-GP wrote:
08 Apr 2023, 04:33
It is minimum a form drag generator because it has a cross section. Furthermore, look at the top of the side pod, the floor leading edge, and everything around the midwing. It's downwashing. This is not rocket science. This is even corroborated by Kyle Engineers (the former Merc aero), and the Vanja/Shub CFD collaboration projects.
Regular side pods have a bigger cross section than it. So this is not the type of drag that would make it worse. the Vortex drag would have to be compared with some sort of CFD or wind tunnel. you just can tell this by eye-balling it.

Funny thing is this year, the Mercedes is slipperier than the Aston Martin so far.
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AR3-GP
AR3-GP
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Re: Mercedes W14

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PlatinumZealot wrote:
08 Apr 2023, 05:17
AR3-GP wrote:
08 Apr 2023, 04:33
It is minimum a form drag generator because it has a cross section. Furthermore, look at the top of the side pod, the floor leading edge, and everything around the midwing. It's downwashing. This is not rocket science. This is even corroborated by Kyle Engineers (the former Merc aero), and the Vanja/Shub CFD collaboration projects.
Regular side pods have a bigger cross section than it. So this is not the type of drag that would make it worse. the Vortex drag would have to be compared with some sort of CFD or wind tunnel. you just can tell this by eye-balling it.

Funny thing is this year, the Mercedes is slipperier than the Aston Martin so far.
I didn’t say the mid wing was more draggy or less draggy than another car.

I was only questioning the theory that it is “aero neutral” by pointing out that it generates drag, even if some do not believe it’s downwashing.
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ringo
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Re: Mercedes W14

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AR3-GP wrote:
08 Apr 2023, 04:47
ringo wrote:
08 Apr 2023, 04:30
The mid wing may be aero neutral or it may generate lift. I suspect if the upstream air of it is not coming to it straight, it can possibly be neutral or by a stretch generate downforce. The air is not hitting it head on like clean virgin air without any 3d considerations. The air is rolling through the control arms, and from over the top of the chassis, then there is the upwash from the front wing.
The net force from the wing depends heavily on the angle of attack, and that is relative to the localized flow vector upstream.
https://cdn.crash.net/styles/large_arti ... 9.0064.jpg
There is no phantom downwash that is occuring ahead of the mid-wing, causing it to generate downforce. Come on, stop it.
How would you know that? I did not say downwash. I said upwash.
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AR3-GP
AR3-GP
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Re: Mercedes W14

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ringo wrote:
08 Apr 2023, 15:48
AR3-GP wrote:
08 Apr 2023, 04:47
ringo wrote:
08 Apr 2023, 04:30
The mid wing may be aero neutral or it may generate lift. I suspect if the upstream air of it is not coming to it straight, it can possibly be neutral or by a stretch generate downforce. The air is not hitting it head on like clean virgin air without any 3d considerations. The air is rolling through the control arms, and from over the top of the chassis, then there is the upwash from the front wing.
The net force from the wing depends heavily on the angle of attack, and that is relative to the localized flow vector upstream.
https://cdn.crash.net/styles/large_arti ... 9.0064.jpg
There is no phantom downwash that is occuring ahead of the mid-wing, causing it to generate downforce. Come on, stop it.
How would you know that? I did not say downwash. I said upwash.
Sorry if that is confusing, I was referring to this post of yours:
ringo wrote:
08 Apr 2023, 04:30
The mid wing may be aero neutral or it may generate lift. I suspect if the upstream air of it is not coming to it straight, it can possibly be neutral or by a stretch generate downforce. The air is not hitting it head on like clean virgin air without any 3d considerations. The air is rolling through the control arms, and from over the top of the chassis, then there is the upwash from the front wing.
The net force from the wing depends heavily on the angle of attack, and that is relative to the localized flow vector upstream.
You said:
I suspect if the upstream air of it is not coming to it straight, it can possibly be neutral or by a stretch generate downforce.
The only way the midwing generates downforce directly is in the presence of a hurricane :lol:

Your second point:
How would you know that? I did not say downwash. I said upwash.
If there is some upwash, then the midwing is definitely generating lift. I don't think there is too much upwash. You can see that the front suspension and the vane on the side of the nose box just ahead of the sidepod inlet are encouraging some downwash and the mid-wing is locally consistent.


I can't see any credible argument that this is "aero-neutral" or "generating downforce". All signs point to the mid-wing being down washing, thus generating some lift. This lift is not an inherent problem with the design. It's a tradeoff.

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Farnborough
Farnborough
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Re: Mercedes W14

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By definition we'd have not much to discuss if this iteration, W14, was competitive with the benchmark RB.

MB know how to make most of the car very well, that experience hadn't just vaporised since WCC success.

Just a process of elimination, they know how to make wings, tub, suspension, etc but currently the team "sphere" of experience has not been ultimately successful within this rules regimen. What does that leave ? Below floor or above floor to really consider.
Most (all across opinion scources) seem to point at things to explain they are in fact working, when something clearly is not. That doesn't yeald a fundamentally good start point when they are looking for a fault.

The W14 so far appears to act like a vehicle with high polar momentum, which it doesn't have from mechanical distribution. Note how it releases and fast at one end or the other, and confirmed by the drivers as difficult to balance. They are loading wing on either end, making it more of a wing focused car than floor type. Its further up the overall order than reality because of the driver skill, but just watch them in fighting it. Its not "centred" in load it seems from the comments the drivers give.

I dont believe they'll see where they really are until they change that mid wing concept.

It'll be interesting to see where their development takes them, I'm looking forward to that certainly.

As reference, but really more for car comparison thread than here. The fastest car looks to me that it has positive load from the car mid section (particularly when sidepods reach peak flow) in comparison to this W14, that car is definitely centralised (uses relatively small wings) in dynamic mass, also the AM but not to such degree.

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ringo
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Re: Mercedes W14

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AR3-GP wrote:
08 Apr 2023, 15:58
ringo wrote:
08 Apr 2023, 15:48
AR3-GP wrote:
08 Apr 2023, 04:47


There is no phantom downwash that is occuring ahead of the mid-wing, causing it to generate downforce. Come on, stop it.
How would you know that? I did not say downwash. I said upwash.
Sorry if that is confusing, I was referring to this post of yours:
ringo wrote:
08 Apr 2023, 04:30
The mid wing may be aero neutral or it may generate lift. I suspect if the upstream air of it is not coming to it straight, it can possibly be neutral or by a stretch generate downforce. The air is not hitting it head on like clean virgin air without any 3d considerations. The air is rolling through the control arms, and from over the top of the chassis, then there is the upwash from the front wing.
The net force from the wing depends heavily on the angle of attack, and that is relative to the localized flow vector upstream.
You said:
I suspect if the upstream air of it is not coming to it straight, it can possibly be neutral or by a stretch generate downforce.
The only way the midwing generates downforce directly is in the presence of a hurricane :lol:

Your second point:
How would you know that? I did not say downwash. I said upwash.
If there is some upwash, then the midwing is definitely generating lift. I don't think there is too much upwash. You can see that the front suspension and the vane on the side of the nose box just ahead of the sidepod inlet are encouraging some downwash and the mid-wing is locally consistent.


I can't see any credible argument that this is "aero-neutral" or "generating downforce". All signs point to the mid-wing being down washing, thus generating some lift. This lift is not an inherent problem with the design. It's a tradeoff.

https://www.autohebdo.fr/app/uploads/20 ... scaled.jpg
It's not as simple as because it's generating downwash downstream its generating lift.

You would have to actually investigate it with cfd or a wind tunnel.

I am just saying I would not come to a conclusion without any real information.

What I do know if the air is coming onto that wing at an angle, say angle greater than the title of the wing, It can indeed generate downforce.
Aerodynamics is very complex, so i do not like to draw conclusions using generic information.

Also of note is the mid wings shape. If you look carefully the lower surface has a longer arc length than the upper surface, which is a good indication that the lower pressure is underneath. Not a definitive law, but just a little rule of thumb or hint.
Last edited by ringo on 08 Apr 2023, 18:11, edited 1 time in total.
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AR3-GP
AR3-GP
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Re: Mercedes W14

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ringo wrote:
08 Apr 2023, 17:13
It's not as simple as because it's generating downwash downstream its generating lift.
This is Newton's 3rd law.
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PlatinumZealot
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Re: Mercedes W14

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AR3-GP wrote:
08 Apr 2023, 17:30
ringo wrote:
08 Apr 2023, 17:13
It's not as simple as because it's generating downwash downstream its generating lift.
This is Newton's 3rd law.
Can't take it in isolation. It could already be part of a downwashing stream or helping a downwashing stream, or even negativing a lifting flow downstream. You need full CFD to know what it is doing.
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ringo
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Re: Mercedes W14

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AR3-GP wrote:
08 Apr 2023, 17:30
ringo wrote:
08 Apr 2023, 17:13
It's not as simple as because it's generating downwash downstream its generating lift.
This is Newton's 3rd law.
Look on the lenght of the arcs on upper and lower surface and compare them. Just another reason why things are not black and white. Usually the longer arc is where you have higher speed and lower pressure.
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Vanja #66
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Re: Mercedes W14

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ringo wrote:
08 Apr 2023, 04:30
The mid wing may be aero neutral or it may generate lift. I suspect if the upstream air of it is not coming to it straight, it can possibly be neutral or by a stretch generate downforce.
I understand what you're saying and I had a bit of an "internal discussion" with myself last year about this. However, I strongly believe this wing would sooner stall than come anywhere close to zero-lift or downforce. The fact remains the rear is very cambered and this alone will always generate higher pressure on bottom than on top surface.
And they call it a stall. A STALL!

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