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Nice find. Can't get much more simple than that.

www.up22.com said:
Wings, by their design require that there be no obstruction between the bottom of the wing and the road surface, for them to be most effective. So mounting a wing above a trunk lid limits the effectiveness.
So does that suggest that something like DavidV's wing is useless? If the wing is high enough and not directly above the trunk, the air would reconnect without being affected by the ground.

Unfortunately, the article doesn't address the special situation with our cars of additional air coming up through the engine lid. I am curious how this changes a wing's effetctiveness on our cars.

This would make a good sticky though for aero newbies. Perhaps an entire sticky just for aero articles.

Here's another one that I liked.
It's located here
 

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mr2pmp said:
Nice find. Can't get much more simple than that.



So does that suggest that something like DavidV's wing is useless? If the wing is high enough and not directly above the trunk, the air would reconnect without being affected by the ground.
The angled trailing edge on my MR2's wing is actually slightly behind the trunk. If you look closely, you'll see that the wing is positioned above the roofline, in the line of clear air, and slightly behind the trunk.



-- DavidV :D
 

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The cars in question are the Lotus Exige and the Noble M400. If you don't know what either of those look like, Google Image Search them. I've supplied a picture of a Lotus Exige. What I'm wondering about is the lip spoiler they have, and then they have a wing on top of that. In this text from the first link that Bill gave us, it says:

Wings are not generally seen in concert with spoilers, as they both occupy similar locations, and defeat each other's purpose.
What I'm getting out of this is that the rear end on the Noble isn't efficient?

Please help me understand this better cause I think Noble and Lotus would be the type of manufacturer to go into the wind tunnel and actually produce something VERY efficient.

 

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They may not be for the purpose of rear downforce. They may be to help guide air to a better path, or prevent turbulance? I also think the 91T MR2 wing is designed for something other than downforce, something like aiding stability in crosswings? At least thats what I think I remember hearing.
 

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DR PH1L said:
The cars in question are the Lotus Exige and the Noble M400. If you don't know what either of those look like, Google Image Search them. I've supplied a picture of a Lotus Exige. What I'm wondering about is the lip spoiler they have, and then they have a wing on top of that. In this text from the first link that Bill gave us, it says:



What I'm getting out of this is that the rear end on the Noble isn't efficient?

Please help me understand this better cause I think Noble and Lotus would be the type of manufacturer to go into the wind tunnel and actually produce something VERY efficient.

Using a wing and a spoiler (think nascar style high angle of attack spoiler) would be inneficient. although the extension of the rear under the wing on the lotus is in fact a spoiler it is probably not what the author is referrring to. his statement was too general. this type of spoiler is really just an extsnion of the rear body panel that extends the point at which the air "drops off" and causes wake infill. the air wants to turn downward and then circle back toward the rear of the car. if this spoiler was not there then the air would be doing this directly beneath the rear wing. the air flow beneath the wing is the most important aspect of the wing. this spoiler is there to increase the efficiency of the wing by ensuring that turbulence is not introduced into the under side airflow of the wing.

if the lotus had a nascar style spoiler under the rear wing, the air on top of the spoiler would cause a high pressure area under the wing and negate or overpower any negative lift that the wing created.

again the guy is using too general of terms
 

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I'd like to point out the surface area and location of the end plates might be important. The end plates on those high mounted wings are pretty large. While the car is going perfectly straight with no crosswind, they cause almost no drag. But, when the car turns (and needs aero help to stay on the road) they provide sideforce* (a word that I just made up...like sideways downforce). They also have a lot of leverage against body roll. The further up and further back they are...the more leverage they have.

Prodrive's Subaru WRC car has sported rear wings with multiple vertical panels to increase this surface area.

Remember, wings provide downforce to the tires to generate a sideforce to keep the rear end from spinning out. Those endplates do it directly.
 

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I'd like to point out the surface area and location of the end plates might be important. The end plates on those high mounted wings are pretty large. While the car is going perfectly straight with no crosswind, they cause almost no drag. But, when the car turns (and needs aero help to stay on the road) they provide sideforce* (a word that I just made up...like sideways downforce). They also have a lot of leverage against body roll. The further up and further back they are...the more leverage they have.

Prodrive's Subaru WRC car has sported rear wings with multiple vertical panels to increase this surface area.

Remember, wings provide downforce to the tires to generate a sideforce to keep the rear end from spinning out. Those endplates do it directly.
Correct me if I'm wrong but, to my understanding, the vertical panels prevent lateral air movement over the wing during very high slip angles (WRC). This insures the most consistant performance from the wing.
 

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endplates (aka end fences) stop air spilling off the sides (or air spilling from underneath the wing around the sides, from high to low pressure areas) and reducing the wings' pressure differential

WRC cars also have plates in the middle of the wing (in between the end plates) called fences which are there to improve the performance of the wing at high slip angles
 

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Big Thurs said:
Correct me if I'm wrong but, to my understanding, the vertical panels prevent lateral air movement over the wing during very high slip angles (WRC). This insures the most consistant performance from the wing.
You are correct. But that's not ALL that they do.
 
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