General aero discussions

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AR3-GP
AR3-GP
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Joined: 06 Jul 2021, 01:22

Re: Mercedes W14

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Vanja #66 wrote:
08 Apr 2023, 19:11
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.
Furthermore, one couldn't understand why Mercedes would go to such great lengths and compromise to their car design (the sidepod and maybe even the cockpit position), so that they can run an "aero neutral" wing device. The arguments are getting a bit silly.

If the aim was to be "aero neutral" then they would never use the wing in the first place. It's a drag generator.
A lion must kill its prey.

mcouto
mcouto
0
Joined: 08 Apr 2023, 19:11

Re: Mercedes W14

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ringo wrote:
08 Apr 2023, 18:13
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.
You have to take in account the wings angle of attack not just it’s shape…

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vorticism
323
Joined: 01 Mar 2022, 20:20

Re: Mercedes W14

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I'm gonna have to start typing relatively in all caps when I use it. I bet a traditional sidepod generates more lift than this mid-wing.

To the discussion above, think of it this way: in a 90* wind tunnel elbow, the turning vanes are heavily cambered. Yet they are aero neutral.
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Farnborough
Farnborough
100
Joined: 18 Mar 2023, 14:15

Re: Mercedes W14

Post

AR3-GP wrote:
08 Apr 2023, 19:19
Vanja #66 wrote:
08 Apr 2023, 19:11
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.
Furthermore, one couldn't understand why Mercedes would go to such great lengths and compromise to their car design (the sidepod and maybe even the cockpit position), so that they can run an "aero neutral" wing device. The arguments are getting a bit silly.

If the aim was to be "aero neutral" then they would never use the wing in the first place. It's a drag generator.
I believe there was correlation last year with W13 in performance at circuit that, predominantly high altitude, the mid wing being fixed geometry effectively became less influence on the overall chassis performance.

In other words, as they pushed more conventional wing onto the car to work in those environments, these start to hold precedent over that fixed mid wing in giving the car a more balance. The performance was obvious in it's movement toward the front of the field, even fooling MB into thinking they were getting some progress. The signs were there if viewed in the right context.

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Vanja #66
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Joined: 19 Mar 2012, 16:38

Re: Mercedes W14

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vorticism wrote:
08 Apr 2023, 19:30
To the discussion above, think of it this way: in a 90* wind tunnel elbow, the turning vanes are heavily cambered. Yet they are aero neutral.
Because they are stacked next to each other and have a different function than wing foils. Convex surface on one influences pressure distribution on the concave surface of the other and so on...
And they call it a stall. A STALL!

#DwarvesAreNaturalSprinters
#BlessYouLaddie

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vorticism
323
Joined: 01 Mar 2022, 20:20

Re: Mercedes W14

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Exactly. They are neutral within predominating flow. The stacking isn't necessarily relevant within the example.

I'm using 'neutral' relatively loosely these last few posts. How about: "shaped in accordance with the local domain."
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AR3-GP
AR3-GP
365
Joined: 06 Jul 2021, 01:22

Re: Mercedes W14

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vorticism wrote:
08 Apr 2023, 19:30
I'm gonna have to start typing relatively in all caps when I use it. I bet a traditional sidepod generates more lift than this mid-wing.

To the discussion above, think of it this way: in a 90* wind tunnel elbow, the turning vanes are heavily cambered. Yet they are aero neutral.
Turning vanes are not "aero neutral". Turning vanes are by definition, turning vanes! They are doing flow turning!

In your example of the elbow, the turning vanes will provide flow turning in order to prevent separation on the inner radius of the elbow.
A lion must kill its prey.

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vorticism
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Joined: 01 Mar 2022, 20:20

Re: Mercedes W14

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Neutral in the sense of them not diverting flow adversarially relative to the local domain and as well not inducing vortices, which is to say, aero neutral in the race-car-with-winglets-everywhere sense. As I said just above, the stacking and flow straightening in a wind tunnel isn't relevant to the point I'm making, which is about the existence of situations where cambered wings can exist within a neutral context. Think of it yet another way: tweak the shape one of those stacked vanes and suddenly you end up with a non-neutral wing, to the extent that a flat zero-camber foil suddenly becomes much draggier/liftier (yw) than a heavily cambered foil.
Last edited by vorticism on 08 Apr 2023, 20:09, edited 1 time in total.
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Farnborough
Farnborough
100
Joined: 18 Mar 2023, 14:15

Re: Mercedes W14

Post

AR3-GP wrote:
08 Apr 2023, 19:59
vorticism wrote:
08 Apr 2023, 19:30
I'm gonna have to start typing relatively in all caps when I use it. I bet a traditional sidepod generates more lift than this mid-wing.

To the discussion above, think of it this way: in a 90* wind tunnel elbow, the turning vanes are heavily cambered. Yet they are aero neutral.
Turning vanes are not "aero neutral". Turning vanes are by definition, turning vanes! They are doing flow turning!

In your example of the elbow, the turning vanes will provide flow turning in order to prevent separation on the inner radius of the elbow.
I'd see that the same, not comparable to flow over vehicle.

Farnborough
Farnborough
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Joined: 18 Mar 2023, 14:15

Re: Mercedes W14

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vorticism wrote:
08 Apr 2023, 20:08
Neutral in the sense of them not diverting flow adversarially relative to the local domain and as well not inducing vortices, which is to say, aero neutral in the race-car-with-winglets-everywhere sense. As I said just above, the stacking and flow straightening in a wind tunnel isn't relevant to the point I'm making, which is about the existence of situations where cambered wings can exist within a neutral context. Think of it yet another way: tweak the shape one of those stacked vanes and suddenly you end up with a non-neutral wing, to the extent that a flat zero-camber foil suddenly becomes much draggier/liftier (yw) than a heavily cambered foil.
Also your example is not measuring the load on those turning vane at their fixing point within the tunnel structure.

AR3-GP
AR3-GP
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Joined: 06 Jul 2021, 01:22

Re: Mercedes W14

Post

vorticism wrote:
08 Apr 2023, 20:08
Neutral in the sense of them not diverting flow adversarially relative to the local domain and as well not inducing vortices, which is to say, aero neutral in the race-car-with-winglets-everywhere sense. As I said just above, the stacking and flow straightening in a wind tunnel isn't relevant to the point I'm making, which is about the existence of situations where cambered wings can exist within a neutral context. Think of it yet another way: tweak the shape one of those stacked vanes and suddenly you end up with a non-neutral wing, to the extent that a flat zero-camber foil suddenly becomes much draggier/liftier (yw) than a heavily cambered foil.
I'm not sure I understand the context. There is nothing on an F1 car whose sole purpose is to be neither lifting/downwashing nor inwashing/outwashing and whose sole purpose is to generate drag.

There is a good video here which hypothesizes on what one might be able to do with a "mid-wing" like device located in the middle of the car. These may not be models of any particular F1 car, but you can see that such a device would be targeted at downwashing and vortex generation.

A lion must kill its prey.

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vorticism
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Re: Mercedes W14

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Farnborough wrote:
08 Apr 2023, 20:11
vorticism wrote:
08 Apr 2023, 20:08
Neutral in the sense of them not diverting flow adversarially relative to the local domain and as well not inducing vortices, which is to say, aero neutral in the race-car-with-winglets-everywhere sense. As I said just above, the stacking and flow straightening in a wind tunnel isn't relevant to the point I'm making, which is about the existence of situations where cambered wings can exist within a neutral context. Think of it yet another way: tweak the shape one of those stacked vanes and suddenly you end up with a non-neutral wing, to the extent that a flat zero-camber foil suddenly becomes much draggier/liftier (yw) than a heavily cambered foil.
Also your example is not measuring the load on those turning vane at their fixing point within the tunnel structure.
I assure you the wind tunnel in question is fully festooned with the latest of high precision load and pressure metrology equipment. This is a technical forum, after all. However, none of that is relevant.

Another example. Draw a pipe sweep at the angle and radius of your choosing. Now, place an airfoil within it which will cause the least amount of pressure drop. Hint: it will be cambered and not flat, despite flat/zero camber airfoils being assumed as the most neutral.

Now, F1 races aren't conducted inside of tubes (yet) of course. However, ask yourself, why are the pitot arrays they place behind tyres and diffusers always arranged in such jaunty and extreme angles? Without there being any jaunty nor extreme flow conditioners nor turning vanes immediately within there vicinity.
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vorticism
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Re: Mercedes W14

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AR3-GP wrote:
08 Apr 2023, 20:19
vorticism wrote:
08 Apr 2023, 20:08
Neutral in the sense of them not diverting flow adversarially relative to the local domain and as well not inducing vortices, which is to say, aero neutral in the race-car-with-winglets-everywhere sense. As I said just above, the stacking and flow straightening in a wind tunnel isn't relevant to the point I'm making, which is about the existence of situations where cambered wings can exist within a neutral context. Think of it yet another way: tweak the shape one of those stacked vanes and suddenly you end up with a non-neutral wing, to the extent that a flat zero-camber foil suddenly becomes much draggier/liftier (yw) than a heavily cambered foil.
I'm not sure I understand the context. There is nothing on an F1 car whose sole purpose is to be neither lifting/downwashing nor inwashing/outwashing and whose sole purpose is to generate drag.

There is a good video here which hypothesizes on what one might be able to do with a "mid-wing" like device located in the middle of the car. These may not be models of any particular F1 car, but you can see that such a device would be targeted at downwashing and vortex generation.
Then were just back at speculating about relativity. How much vorticity and how much 'washing.' Not saying anyone's wrong with there stances here. Some of use are saying, "Not much," and others are saying, "a lot." To me it looks like a "not much" airfoil (that's a doctorate level aerospace term, trust me).
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AR3-GP
AR3-GP
365
Joined: 06 Jul 2021, 01:22

Re: Mercedes W14

Post

vorticism wrote:
08 Apr 2023, 20:24
Farnborough wrote:
08 Apr 2023, 20:11
vorticism wrote:
08 Apr 2023, 20:08
Neutral in the sense of them not diverting flow adversarially relative to the local domain and as well not inducing vortices, which is to say, aero neutral in the race-car-with-winglets-everywhere sense. As I said just above, the stacking and flow straightening in a wind tunnel isn't relevant to the point I'm making, which is about the existence of situations where cambered wings can exist within a neutral context. Think of it yet another way: tweak the shape one of those stacked vanes and suddenly you end up with a non-neutral wing, to the extent that a flat zero-camber foil suddenly becomes much draggier/liftier (yw) than a heavily cambered foil.
Also your example is not measuring the load on those turning vane at their fixing point within the tunnel structure.
I assure you the wind tunnel in question is fully festooned with the latest of high precision load and pressure metrology equipment. This is a technical forum, after all. However, none of that is relevant.

Another example. Draw a pipe sweep at the angle and radius of your choosing. Now, place an airfoil within it which will cause the least amount of pressure drop. Hint: it will be cambered and not flat, despite flat/zero camber airfoils being assumed as the most neutral.

Now, F1 races aren't conducted inside of tubes (yet) of course. However, ask yourself, why are the pitot arrays they place behind tyres and diffusers always arranged in such jaunty and extreme angles? Without there being any jaunty nor extreme flow conditioners nor turning vanes immediately within there vicinity.
This is a great example of aero neutrality but note that the only reason this attempt at aero neutral scaffolding exist, is to hold the probes in the correct location in space. There is no other reason.

Now contrast that to the actual aero devices of an F1 car that is not in a testing spec. What purpose would there be to mount an "aero neutral" wing element anywhere? It would just generate drag.
A lion must kill its prey.

AR3-GP
AR3-GP
365
Joined: 06 Jul 2021, 01:22

Re: Mercedes W14

Post

vorticism wrote:
08 Apr 2023, 20:28
AR3-GP wrote:
08 Apr 2023, 20:19
vorticism wrote:
08 Apr 2023, 20:08
Neutral in the sense of them not diverting flow adversarially relative to the local domain and as well not inducing vortices, which is to say, aero neutral in the race-car-with-winglets-everywhere sense. As I said just above, the stacking and flow straightening in a wind tunnel isn't relevant to the point I'm making, which is about the existence of situations where cambered wings can exist within a neutral context. Think of it yet another way: tweak the shape one of those stacked vanes and suddenly you end up with a non-neutral wing, to the extent that a flat zero-camber foil suddenly becomes much draggier/liftier (yw) than a heavily cambered foil.
I'm not sure I understand the context. There is nothing on an F1 car whose sole purpose is to be neither lifting/downwashing nor inwashing/outwashing and whose sole purpose is to generate drag.

There is a good video here which hypothesizes on what one might be able to do with a "mid-wing" like device located in the middle of the car. These may not be models of any particular F1 car, but you can see that such a device would be targeted at downwashing and vortex generation.
Then were just back at speculating about relativity. How much vorticity and how much 'washing.' Not saying anyone's wrong with there stances here. Some of use are saying, "Not much," and others are saying, "a lot." To me it looks like a "not much" airfoil (that's a doctorate level aerospace term, trust me).
Yes good points, we are only speculating on the strength of the mid-wing. I lean towards not too strong, because it's not even a proper wing. The trailing edge is fat.
A lion must kill its prey.