Ground Effect - Bring It Back

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rjsa
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Re: Ground Effect - Bring It Back

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bhall II wrote:
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Remember: most upwash comes from under the car, through the diffuser, and venturi tunnels would be no different

I recognize that most of this this is probably counterintuitive, and, frankly, I can't necessarily blame anyone for being skeptical. No fans of any sport are more ill-served by its leadership and "the specialized press" that covers it than those who follow F1. Logic is like a foreign language.
Look at the floor pressures on your image. Where is the center of pressure? In the back.

The point discussed by me and a few here is that it must be brought to the cars center of mass. That simple.

And experience proves - from the 80's F1 cars and the CART/IRL up to today - that cars with GE tunnels can race close by. They can pass. On any track. Period. It's there, it's happened, it still happens. No amount of patronzing, CFD images and second hand wisdom will change that.

bhall II
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Andres125sx wrote:Basically because I don´t want to trade one GE solution for another GE solution, but a wing based solution for a GE based solution.

Anycase GE is just an idea, the target is to reduce dirty air problem and you´ve stated yourself there are solutions wich would reduce the problem. Let´s talk about that instead of explaining why this or that solution will never work. I think nobody is defending a particular solution, we only want to discuss about how to reduce the problem as much as posible
The 2009 rule change already shifted performance from wings to ground effect. As it stands, the rear wing is basically the only aerodynamic device on the car that doesn't work like a venturi tunnel. Moreover, its efficacy has been diminished so much over the last few years that it's currently little more than a way to facilitate DRS.

What I've been trying to say here is that I don't think there's a solution beyond complete chassis standardization, and going down that route would only open the door to the mere possibility of increased overtaking. "Dirty air" is the symptom; it's not the disease.

We have to understand that F1 is in a rather unique position when it comes to racing. Driven by goals unrelated to "the show," its historical dynamo is simply incompatible with prolific overtaking...
Tim.Wright wrote:As always, it's close racing or fast racing. You can't have both.
In a spec-series, overtaking works because the prime performance differentiator is an imperfect biological entity, and every single car ostensibly has the capability to win on merit alone. This is not the case in a developmental series like Formula One where there are many potential performance differentiators and all but the driver are capable of near-perfect reliability. That ultimately means a 0.1s advantage is virtually insurmountable until the system that provides it fails, and F1 cars don't fail that often anymore. (Apologies to Renault and Honda.)

If you want to genuinely mitigate the detrimental effects of "dirty air," you have to standardize the entire chassis, because F1 engineers will quickly make a mockery of any and all half-measures. And if you want to guarantee that chassis standardization will increase overtaking, you have to standardize power trains for exactly the same reason. Otherwise, you're just trading one problem for another.

For me, the ideal answer is to restore F1's status as the Great Race Against Possibility. Who gives a --- about overtaking when you have cars flying around Monza at speeds up to 400kp or tackling Silverstone so quickly that g-suits wouldn't necessarily be an unreasonable idea?

Let's allow the cars to be both the tool and the obstacle.
rjsa wrote:Look at the floor pressures on your image. Where is the center of pressure? In the back.

The point discussed by me and a few here is that it must be brought to the cars center of mass. That simple.

And experience proves - from the 80's F1 cars and the CART/IRL up to today - that cars with GE tunnels can race close by. They can pass. On any track. Period. It's there, it's happened, it still happens. No amount of patronzing, CFD images and second hand wisdom will change that.
Prove it. At this point, it's probably more helpful to see it for yourself.

And I'm sorry for being so brusk with you. Like Pastor Maldonado, I'm not especially skilled at toeing the line between assertive and aggressive.

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FW17
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bhall II wrote:Prove it. At this point, it's probably more helpful to see it for yourself.

What do you want proved?

The tunnel car does not leave behind an area of back wash because of the smoother longer tunnel exit in comparison to the diffuser.

Image

Image

bhall II
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The pressure gradient actually comes closer to disproving the idea that a rearward CoP is somehow a fatal flaw, and the pathlines depict roughly the same upwash as F1...

Image

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FW17
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Rearward center of pressure has got nothing to do with it. You can have a GE with the CoP near the rear wheels and extending the exits further behind.

The back wash is the problem with diffuser which is not the case with the tunnel.

Full length tunnel (with CoP at the center of the car) as in the 80's are being suggested so that the over all drag of the car is reduced with lesser reliance on the rear wing with an option to also remove the front wing.

bhall II
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WilliamsF1 wrote:The back wash is the problem with diffuser which is not the case with the tunnel.
I don't know what this means. Are you trying to say there's a substantial difference between the wake of a venturi tunnel and that of a diffuser? 'Cause that's not even remotely true.

Beyond that, the low-pressure wake from everything above and around a diffuser/venturi tunnel can influence upwash as much as anything else, and designers are exploiting that more and more to increase underbody aero efficiency.

Everything I've pointed out is designed to c̶r̶e̶a̶t̶e̶ ̶a̶n̶ build upon the upwash from under the floor...

Image

The idea is to form a "pocket" that both enhances pressure recovery and helps "drive" the rear wing.

EDIT: better phrasing
Last edited by bhall II on 29 Jul 2015, 12:17, edited 1 time in total.

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FW17
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All things are pointing up so that the pressure difference behind the car is reduced to make the diffuser more efficient

In the 2000's the rear wing (low) and beam wing did the job of up wash to increase the diffuser

Now it is all the appendages that you have pointed out

Without the upwash it will only make the back wash (the reversal of diffuser air flow back into the low pressure zone) are more of an issue and lowers the efficiency of the diffuser

The tunnel is a different story as the air is already in an up wash trajectory increasing the upwash further behind the car will not increase the efficiency of the tunnel.

rjsa
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Re: Ground Effect - Bring It Back

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bhall II wrote:
rjsa wrote:Look at the floor pressures on your image. Where is the center of pressure? In the back.

The point discussed by me and a few here is that it must be brought to the cars center of mass. That simple.

And experience proves - from the 80's F1 cars and the CART/IRL up to today - that cars with GE tunnels can race close by. They can pass. On any track. Period. It's there, it's happened, it still happens. No amount of patronzing, CFD images and second hand wisdom will change that.
Prove it. At this point, it's probably more helpful to see it for yourself.

And I'm sorry for being so brusk with you. Like Pastor Maldonado, I'm not especially skilled at toeing the line between assertive and aggressive.
You prove it. I don't need to prove anything, just to tune in an Indy race.

And again, what do you want? What do you propose?

It seems to me you are just practicing for the high school debate team.

rjsa
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Re: Ground Effect - Bring It Back

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bhall II wrote:The pressure gradient actually comes closer to disproving the idea that a rearward CoP is somehow a fatal flaw, and the pathlines depict roughly the same upwash as F1...

Image
Oh, so now we do have a backwards center o pressure?

And what does another random image is proving? It's got nothing to do with underfloor pressure. It's about wing/difffuser coupling and wake turbulence.

bhall II
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Re: Ground Effect - Bring It Back

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WilliamsF1 wrote:In the 2000's the rear wing (low) and beam wing did the job of up wash to increase the diffuser

Now it is all the appendages that you have pointed out
I amended my post, because I don't want to create any more confusion here due to poor phrasing.

The beam wing and the elements I pointed out do not create the upwash. That occurs because of the shape of the diffuser/venturi tunnel, and it will happen unless deliberately prevented, which would also have a massively negative impact on underbody efficiency.
vonk wrote:Image
Remember this dumbass proposal?

Image

In the same way teams use VGs mounted along the top of the sidepods, the OWG suggested that stupid downwash wing as a way to reduce upwash, thus cementing F1's legacy as a strangely large collection of folks who probably don't know their ass from a hole in the ground. This kinda --- blows my mind.

"Hey, let's enhance underbody downforce."

Yeah, and we should also kill underbody downforce.

:wtf:
rjsa wrote:It seems to me you are just practicing for the high school debate team.
And with all due respect, it seems to me this stuff is waaaay over you head.

Image

Do you understand me now?

rjsa
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Clear. You're clueless, juvenile. Dumb. It's Einstein. Over & out.

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FW17
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Re: Ground Effect - Bring It Back

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bhall II wrote:
WilliamsF1 wrote:In the 2000's the rear wing (low) and beam wing did the job of up wash to increase the diffuser

Now it is all the appendages that you have pointed out
I amended my post, because I don't want to create any more confusion here due to poor phrasing.

The beam wing and the elements I pointed out do not create the upwash. That occurs because of the shape of the diffuser/venturi tunnel, and it will happen unless deliberately prevented, which would also have a massively negative impact on underbody efficiency.
Remember this dumbass proposal?

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

In the same way teams use VGs mounted along the top of the sidepods, the OWG suggested that stupid downwash wing as a way to reduce upwash, thus cementing F1's legacy as a strangely large collection of folks who probably don't know their ass from a hole in the ground. This kinda --- blows my mind.

"Hey, let's enhance underbody downforce."

Yeah, and we should also kill underbody downforce.

:wtf:
rjsa wrote:It seems to me you are just practicing for the high school debate team.
And with all due respect, it seems to me this stuff is waaaay over you head.

http://i.imgur.com/veKy9Jb.jpg

Do you understand me now?
Down wash wing was created by Writh Research

Teams opposed it

Meeting with all teams were called; too many proposals were put forward

Charlie got confused

OWG was created after the teams with only top 3 teams (Ferrari, Renault and McLaren)

OWG proved down wash wing will not work and cause more issues

OWG suggested raising the rear wing and wider front wing as a counter proposal after fondmetal wind tunnel tests with Ferrari supplied 25% models

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djos
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Re: Ground Effect - Bring It Back

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Bhall you are doing a great job of erasing any respect others had for you!

*slow claps*
"In downforce we trust"

bhall II
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WilliamsF1 wrote:Down wash wing was created by Writh Research...
I don't question the origin of the idea; I question why anyone ever thought it was a good one. (The Wirth thing makes sense, though, given his inexplicable all-cfd approach at Virgin.)

If you want to increase overtaking by shifting a greater percentage of downforce creation to ground effect, it doesn't make any sense to turn around and suggest a device that would seriously hamper underbody performance, yanno?

And those little winglet-things would have stalled constantly due to the adverse pressure gradient caused by the spinning wheels directly in front of them.

The whole thing never made sense.
djos wrote:Bhall you are doing a great job of erasing any respect others had for you!

*slow claps*
Yep, I'm fully aware it doesn't look good. Everyone has a limit, though.

That dude's only contribution to this discussion has been an obstinate refusal to accept anything that might counter his thesis, one for which he's not made so much as a token effort to explain.

He's criticized my "random" illustrations, but then tells me to tune to an IndyCar race after I pressed him for justification to back up his views. "[He doesn't] need to prove anything."

He's repeatedly asked for a proposal of my own as if my entire argument here hasn't been totally focused on saying that a solution doesn't necessarily exist.

I apologized for being a dick, because I know this whole thing doesn't reflect well on anyone, and his response was to insult me.

Add it all up, and it seems I've been dealing with an obtuse hypocrite who lacks the courtesy to acknowledge my point of view, let alone understand it.

So, yeah. --- him. I'd learn more from watching flies copulate.

rjsa
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Re: Ground Effect - Bring It Back

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rjsa wrote:
Just_a_fan wrote: ...

Ok, how do you do it? Please note, F1 cars are already in ground effect. They don't run the cambered undersides and skirts of the classic "ground effect cars" but they still make use of ground effect. Any wing placed within its own chord length of the ground will experience "ground effect" and the closer you run it - to a point - the more the effect increases the downforce produced.

Now, you could go back to tunnels and skirts but I'm not sure how else you could implement "ground effect" and have a hope of running close together.
Yes, but only by very hard manouvering around the rules.

The diffuser only exists because the rules were badly written back in the 80s. Rules say floor must be flat between the axles. That because floors never went backwards than that and who in hell would raise the nose, right? And the insane rake angles.

Now you're about to re-write the rules, force a pair of standard tunnels on the sidepods or even make the diffuser go forward and bring it's choke point on top of the mass center. Now just tune back the wings. Smash those almost flat, two elements max. Wider and lower rear, bring the front ones within the wheels where they are supposed be.

Image

And enforce minimum hide height, kill the rake and even get rain racing back in the process.

Here's mine :wink: .