Ferrari F14T

[flyboy2160]

Once again, the car threads are about actual parts on the car, not about driving styles. Those posts were moved to the Team thread.

[bhall II]

I'm not entirely sure. When the wheel is turned, one part of the wing is blocked less, while the other is not. This leaves for a inconsistency in downforce production when the steering is changed(as you have pointed out). I find it hard to figure out of they actually make more downforce when turning because of this inconsistency.

It's inevitable. Think of it this way: when the front wheels are aligned straight, the efficiency of both end plates is compromised, and the front wing's total downforce production reflects that. When the steering angle changes, the blockage behind the outside end plate is removed, which increases its efficiency. At that point, you have one compromised end plate and one uncompromised end plate. In other words, the efficiency of one end plate stays the same while the other becomes more efficient. Combined, it results in a net downforce gain. I think.

I'm pretty sure teams have been doing this since 2009 with varying levels of success. In fact, one could probably make a reasonable argument that outwash front wings made a bigger impact that season than double-diffusers. (But, it won't come from me.)

They both will still have the same area of blockage. The W05 wing has less wing area to create downforce on. Thus I'd say is less affected by these changes(Is that exactly what you are saying?) in steering, or even pitch.

Maybe these images will make it easier to see. (The last image is the McLaren front wing for added context.)

I think it's pretty clear which one is likely to produce bigger wake. So, while you're absolutely correct to point out that all front wings will experience the same blockage, the bigger wake created by Mercedes' wing, and others like it, means steering angle doesn't have to change as much for wing efficiency to increase. Again, I think this is where the trade for consistency comes into play.

Seeing how these outboard wings(And they certainly did last year) create a low pressure zone on the outside of the wing this pulls the dirty air from the wheel with it, away from the floor. This is beneficial further down the car as the floor isn't affected as much from the dirty air from the front wheels. It's not surprising that teams experiment by ducting air through the front brake/hub assembly to augment this.

I might have different thoughts on that. This paper on wheel-wing interaction draws somewhat different conclusions. In short, teams try to use the vortex on the outside edge of the tire's contact patch to "pull" air flow over/under the wing, not the other way around. Nonetheless, the details of that particular discussion are way over my head, because we'd have to start talking about brake ducts and whatnot, and I haven't updated my bio-CFD to the latest release yet.

[f1316]

One thing I don't understand, however, is that last season I distinctly remember Ferrari saying that they had stopped chasing maximum peak downforce in favour of more consistent downforce.

If their philosophy is consciously as described in this thread, that would imply that they'd changed their minds again and are back to a more 'peaky' approach.

I just wonder if that's actually true or, rather, is it the case that they think this approach still gives more consistent downforce in conjunction with their overall design philosophy than the Merc-style FW?

Looking at the nose of the car, I've always been under the impression that they're likely to be getting a good amount of front downforce anyway and that their issue is more balancing this at the rear, so you'd imagine they'd be less concerned with producing lots of - less consistent - downforce at the front of the car.

[turbof1]

I have difficulties to believe this theory. Sorry bhall, it's a well thought-through hypothesis, but it has hiates.

-The biggest issue is that a turned wheel, while having less influence on the front wing itself, creates a blockade on the outside of the wing for airflow going around the tyre. The is airflow is critical for rear downforce. What you gain in front, is what you'll loose at the rear, creating imbalance.

-While teams very much attempt to have consistent downforce and try to achieve this through keeping the wheel wake from influencing the FW, there's also a secondary use: wheel wake is very, very draggy. On straights you want to keep airflow from hitting the tyre because every bit of volume that can be avoided, will be avoided. Even at the cost of peak downforce.

-If we follow your hypthesis, then one wheel will be turned outboard and the other inboard. The latter creates a larger blockade then in non-turned stance.

Teams obviously do consider how a turned wheel influences the airflow and downforce consistency, but I think it's more a case of finding ways to get airflow around an outwards turned wheel.

My honest opinion? Ferrari have a bigger span because they have to keep the wing simple. If they try something more complex, they get lost in correlation issues.

[trinidefender]

I have difficulties to believe this theory. Sorry bhall, it's a well thought-through hypothesis, but it has hiates.

-The biggest issue is that a turned wheel, while having less influence on the front wing itself, creates a blockade on the outside of the wing for airflow going around the tyre. The is airflow is critical for rear downforce. What you gain in front, is what you'll loose at the rear, creating imbalance.

-While teams very much attempt to have consistent downforce and try to achieve this through keeping the wheel wake from influencing the FW, there's also a secondary use: wheel wake is very, very draggy. On straights you want to keep airflow from hitting the tyre because every bit of volume that can be avoided, will be avoided. Even at the cost of peak downforce.

-If we follow your hypthesis, then one wheel will be turned outboard and the other inboard. The latter creates a larger blockade then in non-turned stance.

Teams obviously do consider how a turned wheel influences the airflow and downforce consistency, but I think it's more a case of finding ways to get airflow around an outwards turned wheel.

My honest opinion? Ferrari have a bigger span because they have to keep the wing simple. If they try something more complex, they get lost in correlation issues.

About the wing being simpler, I think you are over thinking this. Their wing actually has a lower angle of attack than the mercedes and RB wing etc. The main inside planes of the wing do not go to the maximum height and with the lower angle of attack will generate less downforce but as a result have a less turbulent effect on the airflow going on the inside of the wheel. Essentially less work is being done to the airflow there. However on the outside sections yes the span is wider. This is to make up for the slight downforce reduction from the inside section of the wing while sacrificing a bit of flow going outward of the front tyre.

In simple terms, the inside section of the wing creates less turbulent airflow and less downforce while the outside section of the wing has more downforce and more of a vertical component to the airflow unlike the more horizontal force to the airflow as on other cars such as the Mercedes. Simply a different methodology of thinking.

[bhall II]

One thing I don't understand, however, is that last season I distinctly remember Ferrari saying that they had stopped chasing maximum peak downforce in favour of more consistent downforce.

If their philosophy is consciously as described in this thread, that would imply that they'd changed their minds again and are back to a more 'peaky' approach.

[...]

Quick and dirty: low-radius outer wing = consistent downforce; high-radius outer wing = more downforce

Take the W05 as an example of consistency.



The RB10 is an example of more downforce.



The nearly-straight outer wing of the F138 represented an attempt for more downforce.




The F14T, on the other hand, has a lower radius than its predecessor.



In other words, the F14T attempts to make more consistent downforce than the F138, but it still attempts to make more downforce than the W05. Everything is relative.

[bhall II]

I have difficulties to believe this theory. Sorry bhall, it's a well thought-through hypothesis, but it has hiates.

-The biggest issue is that a turned wheel, while having less influence on the front wing itself, creates a blockade on the outside of the wing for airflow going around the tyre. The is airflow is critical for rear downforce. What you gain in front, is what you'll loose at the rear, creating imbalance.

-While teams very much attempt to have consistent downforce and try to achieve this through keeping the wheel wake from influencing the FW, there's also a secondary use: wheel wake is very, very draggy. On straights you want to keep airflow from hitting the tyre because every bit of volume that can be avoided, will be avoided. Even at the cost of peak downforce.

-If we follow your hypthesis, then one wheel will be turned outboard and the other inboard. The latter creates a larger blockade then in non-turned stance.

Teams obviously do consider how a turned wheel influences the airflow and downforce consistency, but I think it's more a case of finding ways to get airflow around an outwards turned wheel.

My honest opinion? Ferrari have a bigger span because they have to keep the wing simple. If they try something more complex, they get lost in correlation issues.

I'm not exactly clear on what you're trying to say, so if I miss something, let me know.

- Until someone figures out how to steer a car without momentarily altering the alignment of the front wheels, steering will always have a dynamic effect on downforce. It's inevitable.

- Teams use cascades, in part, to deal with drag associated with the front wheels.



I just found this in which Gary Anderson actually talks about it. (Given how little I ordinarily think of his analysis, I don't know if this is a good thing or a bad thing.)

And finally, you too should check out this paper. It says a whole lot about this very subject.

[trinidefender]

One thing I don't understand, however, is that last season I distinctly remember Ferrari saying that they had stopped chasing maximum peak downforce in favour of more consistent downforce.

If their philosophy is consciously as described in this thread, that would imply that they'd changed their minds again and are back to a more 'peaky' approach.

[...]

Quick and dirty: low-radius outer wing = consistent downforce; high-radius outer wing = more downforce

Take the W05 as an example of consistency.

http://i.imgur.com/irHij8a.jpg

The RB10 is an example of more downforce.

http://i.imgur.com/RP0BIUM.jpg

The nearly-straight outer wing of the F138 represented an attempt for more downforce.

http://i.imgur.com/PS7Zm6N.jpg
http://i.imgur.com/lJwaL8Q.jpg

The F14T, on the other hand, has a lower radius than its predecessor.

http://i.imgur.com/7qvHtV5.jpg

In other words, the F14T attempts to make more consistent downforce than the F138, but it still attempts to make more downforce than the W05. Everything is relative.

I think the term "reductio ad absurdum" fits here. Saying that a low radius outer wing results in more consistent downforce while saying that a high radius outer wing results in more peaky downforce is simply a flat out fallacy. Please for the love of the world please explain where you got this theory from?

In simple terms having a wing with a wider span means that the effective surface area of the wing is larger meaning for a certain downforce you can run a lower angle of attack or a shorter chord wing reducing turbulence behind the wing. The main purpose of moving airflow outside of the front tyres is to reduce drag and to reduce turbulence coming off of the front tyres. This turbulence hurts downforce creation at the back. As cars these days are rear downforce limited this is very important hence the drive to push air around to the outside of the tyre.

At the same time the designers want to do two things with the airflow going inside of the front wheels. Minimise the turbulence created by the front wing for obvious reasons and also to create very specifically sized and controlled vortices the flow around the side of the side-pods and flow to the edge of the floor to seal the sides of the floor.

[turbof1]

What Gary said in that piece was right (not often I say that about him), but again the conclusion is that the cascade is one tool, not the tool.

It's also essential to understand wheel drag. It comes in 2 forms: drag merely evoked by the blockade the wheel presents, but also the drag coming from it's multiple and huge vortices (and these vortices are unwanted for the record).
I advice you to read this: http://mccabism.blogspot.be/2012/07/whe ... ction.html

- Until someone figures out how to steer a car without momentarily altering the alignment of the front wheels, steering will always have a dynamic effect on downforce. It's inevitable.

True, but doesn't stop teams trying to negate the negative effects. Until this year they had a very large wing at their disposal that even when turning covered the wheel most of the time. This year that is of course lessened, but teams will still try to push airflow around the wheel, reconnecting it back at the base of the sidepods, even when turning (especially when turning). It gives maximal airflow on top of the floor, minimal to the wheel (well atleast that is the intent).

[bhall II]

I think the term "reductio ad absurdum" fits here. Saying that a low radius outer wing results in more consistent downforce while saying that a high radius outer wing results in more peaky downforce is simply a flat out fallacy. Please for the love of the world please explain where you got this theory from?

[...]

Please read everything I've said on the subject, not just my admittedly quick and dirty reply to a question. By not repeating everything I've said every time I respond to something, I'm operating on the assumption that others have been following the entire conversation.

[bhall II]

What Gary said in that piece was right (not often I say that about him), but again the conclusion is that the cascade is one tool, not the tool.

[...]

This is the part I wanted you to see in the Gary Anderson piece.

[turbof1]

Yeah, I agree with him except that. But more importantly, he's talking about pre-2014 wings. While 15cm doesn't seem much, it moved the edge of the wing right in the middle of the tyre. How representative is the article and its content still?

Btw, in a twist of irony I seemly quoted an article that took the essential out of the paper you asked me to read. So I already was aware of the paper, just in a more chewed form.

[bhall II]

I noticed that. McCabism is where I got the paper in the first place!

In any case, what I'm describing is what "outwash" has always meant. It just got reduced in conversation to somehow mean "drag reduction." I mean, it is drag reduction in a sense, because the wings don't inflict a big induced drag penalty along straights, as they're not at full efficiency. But, it's mostly about maximizing downforce within rules that made it easy to dump air flow around the outside of the wheels. In fact, the new narrower wings are a direct response to the massive downforce created by the 2009-2013 outwash designs.

[turbof1]

I noticed that. McCabism is where I got the paper in the first place!

In any case, what I'm describing is what "outwash" has always meant. It just got reduced in conversation to somehow mean "drag reduction." I mean, it is drag reduction in a sense, because the wings don't inflict a big induced drag penalty along straights, as they're not at full efficiency. But, it's mostly about maximizing downforce within rules that made it easy to dump air flow around the outside of the wheels. In fact, the new narrower wings are a direct response to the massive downforce created by the 2009-2013 outwash designs.

Well, you have outwash the drag reductor, but you also have outwash the bend-air-around-the-tyre-to-reconnect-behind-it thingy, and outwash the expansion of air to make a wing larger then it is. I think we are talking among people who are clear-minded enough to understand that.

How are we going to dial this all back to the F14T wing?

[trinidefender]

I think the term "reductio ad absurdum" fits here. Saying that a low radius outer wing results in more consistent downforce while saying that a high radius outer wing results in more peaky downforce is simply a flat out fallacy. Please for the love of the world please explain where you got this theory from?

[...]

Please read everything I've said on the subject, not just my admittedly quick and dirty reply to a question. By not repeating everything I've said every time I respond to something, I'm operating on the assumption that others have been following the entire conversation.

I understand that you are talking about steering angle change and how it effects the downforce created by the front wing but you are only thinking in 2D of moving the air outside the wheel laterally. Airflow is a 3D concept, the airflow can move up and over or up and to he side more which is what I think Red Bull and Ferrari are trying to do more than just move the air laterally what Mercedes and McLaren to a large degree are doing with their philosophy.

By how they looks it seems the Red Bull cars are very drivable as well as being on rails which is what makes them so fast in the corners. Yet this doesn't agree with your theory so guess which one I'll agree with.

Your argument makes SOME sense for downforce created on the side of wing on the outer wheel but not for the side of the FW in front of the inner wheel. The more downforce the side of the wing on the inside of the corner when the wheel is turned means the flatter the car will take the corner and more evenly the load of the car will be distributed. Think about both sides of the wing. The wider span wings such as Ferrari and Red Bull look to me as if they will work better on the side of the car on the inside of the corner as the wheel moves away from the front wing freeing up more of wing to work on purely producing downforce.

It is a balancing act between the side of the wing on the inside of the corner and the side of the wing on the outside of the corner.