Group consensus needed of this aero feature

[j-c-c]

Any ideas of what the purpose is of the small upper rearward notch is pictured here on the Dodge Viper carbon fiber rear wing, on both side end plates of their track/competition ready car?

My first guess is it is vortex oriented, but to cause or reduce the effect?
It is also found on some other applications/makes.
So before I "Monkey see, Monkey do", I'd like to know what tail I am chasing, likely

[freebeard]

At this time in this location --- the attachment does't load so the thumbnail is all there is to go on.

If the notch is at the topmost rear corner, it appears to be one end of a tab. So what is the tab for? The end plate is dark so there is no way to tell, but if the rear fastener is in a slot, that would make the angle of attack adjustable over a reasonable range demarcated by the tab.

Beyond that, I got nuthin'.

[j-c-c]

Thanks
There is no 'tab' in play here. The pictured notch has no mechanical interaction with anything.

The pictured side plate does have a per side single 'pivot' mounting point, and an additional "slot:", which I believe allows this pictured end plate to be releveled anytime the wing angle of attack is reset, when at rest for changing the required downforce generated/needed by the rear wing.

The endplate adjustable slot would allow maintaining visual "correctness" by maintaining the level ground plane reference of the end plate, but I suspect the end plate is most useful in its designed task if oriented parallel to ambient air flow, no matter what the wing angle is adjusted to, and maybe helping the original point of this thread, the "notch" do whatever job it is designed for.
Which is still undetermined.

[Logic]

At a guess the big end plates on race cars are more about using aero to get the rear back in line if/when you lose rear traction.
ie: A vertical wing that helps get the rear back in line.

Compare to this Dodge viper wing:


It looks like someone just superimposed a vertical wing to that wing.

What does my head in (aerodynamically) is the sharp 90 degree edges they leave on these things.
I mean how much effort would it be to aero the aero!?

[j-c-c]

I agree with the lack of any aero shaping of the flat end plate edges.
The primary purpose of the end plates is to prevent air past the wings ends from migrating under and into the high velocity low pressure area under the wing reducing its downforce primary objective. It is a well-known and common solution and even seen to a degree on modern commercial aircraft wing tips.

However, the main question I presented here is still unanswered, what is the very intentional small "notch" for in the upper corner of the end plate.

[freebeard]

If you drew a red circle around it we'd know what you're talking about.

However, the main question I presented here is still unanswered, what is the very intentional small "notch" for in the upper corner of the end plate.

"So what is the tab for?"

"The pictured side plate does have a per side single 'pivot' mounting point, and an additional "slot:", which I believe allows this pictured end plate to be releveled anytime the wing angle of attack is reset, when at rest for changing the required downforce generated/needed by the rear wing."

????

[Logic]

Originally Posted by j-c-c

I agree with the lack of any aero shaping of the flat end plate edges.
The primary purpose of the end plates is to prevent air past the wings ends from migrating under and into the high velocity low pressure area under the wing reducing its downforce primary objective. It is a well-known and common solution and even seen to a degree on modern commercial aircraft wing tips.

However, the main question I presented here is still unanswered, what is the very intentional small "notch" for in the upper corner of the end plate.

Ye; fully aware of wing tip vortices.

But if you wanted the best aero on your wing the end plates would look far more organic and bird like:


Picture the large vertical surfaces relative to oncomming wind direction if you come out of a corner sideways.
The weather-cocking effect helping to get/keep the car back/more in line makes for faster laps.

ie: These vertical components of the wing may look like they're there just to hold the horizontal bits, but they're no-ot!!

[j-c-c]

"So what is the tab for?"

????

Yellow circle denotes the intentional "notch" in this discussion.

And to keep the discussion focused, IMO, there are some end plates that serve dual primary purposes of including to support the wing, the aircraft wing tip comparison I shared here overlooks the important aspect that most high speed aircraft have swept wings (relatively low speed cars seldom do) and are seeking somewhat different ultimate goals with wing tips.

The very slight contribution end plates give in the size pictured in this discussion for directional stability is rather minor, and that purpose offsets the original wing's purpose in that large end plates block air flow to the wing in yaw, reducing down force when down force is most needed.

High speed aero directional stability on a high-performance vehicle has so far been best addressed/improved by center located vertical spines/fin, that has fewer downsides and can double as a primary wing support apparatus in a more robust location (center) and is better able to absorb the maybe thousand lbs? of force the wing generates vs nearer the outer edges of the rear tires, depending on current at the time wing width rules/restrictions.

[Logic]

Originally Posted by j-c-c

Yellow circle denotes the intentional "notch" in this discussion.

And to keep the discussion focused, IMO, there are some end plates that serve dual primary purposes of including to support the wing, the aircraft wing tip comparison I shared here overlooks the important aspect that most high speed aircraft have swept wings (relatively low speed cars seldom do) and are seeking somewhat different ultimate goals with wing tips.

The very slight contribution end plates give in the size pictured in this discussion for directional stability is rather minor, and that purpose offsets the original wing's purpose in that large end plates block air flow to the wing in yaw, reducing down force when down force is most needed.

High speed aero directional stability on a high-performance vehicle has so far been best addressed/improved by center located vertical spines/fin, that has fewer downsides and can double as a primary wing support apparatus in a more robust location (center) and is better able to absorb the maybe thousand lbs? of force the wing generates vs nearer the outer edges of the rear tires, depending on current at the time wing width rules/restrictions.

Look at my pic then look at yours. Mine-yours, mine-yours...
I looks like someone took mine and simply added another less wide piece over the top.
Then the notch is just a consequence of that.

However; Formula 1 does seem to have similar notches, so ???

I dont see an explanation here:
https://www.presticebdt.com/the-aero...cfd-explained/

This video does mention it at around 3 min 30s:

https://www.youtube.com/watch?v=qwu5Vz6zjnM

Seems the higher pressure outside the end plate tries to get into the low pressure area under the wing at the notch, causing an opposite, cancelling vortex.
Thx: I learned something new today!

More F1 pics etc

Still; that added piece has little to do with decreasing tip vortices and more to do with limiting/stopping oversteer/broadsiding/yaw or whatever it's called when a race car loses rear traction when accelerating out of a corner etc IMHO.

[j-c-c]

I am unclear as to what you describe as an "added piece". I have seen in person over many years rear wing end plates and have never seen a laminated? added piece resulting in the notch profile in question with a "tab" look..

Furthermore, we are going to have to just disagree on the merits or lack of merits of the Viper sized end plates offering much help in correcting unintentional yaw. Also, it appears the current F1 wing supports/endplates have nearly tripled? in surface area and now may play a part in high-speed yaw stabilization.

It does appaer the notch in question, if I understand your interesting linked video, plays an active part by creating a countering acting vortex to the vortex created by the louvers added upstream and below the notch.

That then begs the question, what benefit is had if there are no louvers, as seen in my original post?

A bit unrelated, your first link in opening remarks states:
"The rear wing does not work exploiting the ground effect"
That makes little sense, as a properly placed rear wing greatly enhances ground effects down force when using a rear diffuser.