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Active aero experiment

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Old Sep 25, 2022 | 06:03 AM
  #1  
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Default Active aero experiment

I have decided to start posting progress of my active aero experiment on here in case anyone is interested in following along. I am using a 69” NRG wing which isn’t the most effective track wing but the idea is the same for other wings with similar designs. I am trying to keep this experiment as cheap and “simple” as possible so this means lots of Brian power haha. I have seen Keith from flying miata try this out and I am sticking to use the NA headlight motors but mount them inside the trunk. I came up with a way similar to a rocker arm suspension setup using 1/4” aluminum sheet, it’s a work in progress but hopefully everything falls into place. Pics attached, updates to come.


Old Sep 25, 2022 | 06:47 AM
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What application?

That AoA seems far too aggressive for track work, do you need active aero for autocross? The principle is sound, but you need to work with the wing's L/D curves to determine the range of movement required. Typically the low drag AoA would be around 0*. At your highest AoA, you need to tuft test for stalling of the underside at the speeds you want max DF, if there is stalling you need to work backwards find the angle that maintains attached airflow, that will be max available DF for that wing at that speed. That will give you the range of movement you will need to accommodate between the two extremes of low drag low DF and high DF high drag. There are other ways of doing it, but that will work and not require lots of $$$

Looking forward to the updates!
Old Sep 25, 2022 | 10:12 AM
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I don't understand what is the purpose of this active aero? Air brake? Drag reduction system?
From the pictures it seems more like an air brake with the down position being standard, and then lift up the rear under braking. The up position seem very aggressive. This wouldn't be good for cornering, because you appear to significantly increase the frontal area of the wing, and your lift:drag ratio is probably pretty terrible also. And also you want the standard position to be balanced, so if it's 'off' then it's not a suicidal oversteery machine.
If you're going for a DRS style system, then you're going to want to drop the rear to take all the rake out of the wing.
Old Sep 25, 2022 | 10:26 PM
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[QUOTE=Gee Emm;1628449]What application?

That AoA seems far too aggressive for track work, do you need active aero for autocross? The principle is sound, but you need to work with the wing's L/D curves to determine the range of movement required. Typically the low drag AoA would be around 0*. At your highest AoA, you need to tuft test for stalling of the underside at the speeds you want max DF, if there is stalling you need to work backwards find the angle that maintains attached airflow, that will be max available DF for that wing at that speed. That will give you the range of movement you will need to accommodate between the two extremes of low drag low DF and high DF high drag. There are other ways of doing it, but that will work and not require lots of $$$

Looking forward to the updates![/QUOTE

for now this application is only for braking which is why the AOA is so aggressive when fully extended so the wing acts as an air brake. I am amateur when it comes to aero but it is fun to learn and experiment with. Maybe someone with more knowledge can use this information, who knows.
Old Sep 25, 2022 | 10:30 PM
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Originally Posted by engineered2win
I don't understand what is the purpose of this active aero? Air brake? Drag reduction system?
From the pictures it seems more like an air brake with the down position being standard, and then lift up the rear under braking. The up position seem very aggressive. This wouldn't be good for cornering, because you appear to significantly increase the frontal area of the wing, and your lift:drag ratio is probably pretty terrible also. And also you want the standard position to be balanced, so if it's 'off' then it's not a suicidal oversteery machine.
If you're going for a DRS style system, then you're going to want to drop the rear to take all the rake out of the wing.
yes, air brake.. Ideally it would be nice to have the wing move to good positions during cornering but for now it will be used as an air brake to keep it simple. Maybe in the future I will try to dial it in during the corners.
Old Apr 4, 2023 | 04:15 PM
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Very cool. Have you found something that would be a good actuator for it? I am working on something similar, but the only things I can find to actuate it move too slow like 1-2 inches per second.
Old Jun 13, 2023 | 02:36 PM
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Saw this -thought it was an interesting way to do active aero:

https://www.carbonmiata.com/shop/maz...-miata-na-mk1/
Old Jun 13, 2023 | 05:56 PM
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Way to go - in the interests of aero efficiency put draggy boxes in the air stream. Picky I know, and I'm sure they could be relocated inside the boot or even hung off the back of the mount feet.

I didn't see anything about controlling the angle, is it manual, brake/accelerator operated, ECU operated, GPS ... ?

If anyone buys this, please post your experience!
Old Jun 18, 2023 | 02:45 PM
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Do some research on the old Mitsubishi 3000GTs. They had active aero on the first models (90-92?) So I'm not sure how they were controlled but if you could find an old spoiler from one then maybe those motors would be more adaptable.

Another option is to use a stepper motor such as an HVAC blend door motor. Small, easy to configure however the response time may not be fast enough.

Controlling it could be done through Tuner studio. You could set parameters such as brake input or speed settings to activate the spoiler. Or use MS as a reference through canbus with a spoiler controller for sensor information.
Old Jun 23, 2023 | 11:18 AM
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PFI Speed just added active aero to a Honda Civic Drag car, this is apparently getting much more popular on the drag scene. Here is the YT video:
Old Jul 20, 2023 | 05:59 PM
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I always thought it would be fun to use the headlights (barn doors) in conjunction with the rear wing as an air brake. Not sure how aero effective that is, but it would look sweet.
Old Jul 20, 2023 | 06:38 PM
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Us hydroplane guys have been doing active aero for years, decades i believe.
There are many different ways to do it. Many different control methods.
First and foremost, you need to have a good understanding of what the wing is doing, what it needs to do, how fast it needs to do it, and when it needs to do it. I can't help you with that, but all of those factor into the system you build.
I'm interested in seeing what that flimsy *** piece of sheet metal does on that PFI car.

Mine wing is electric, controlled by my thumb with a momentary toggle switch on the steering wheel. Lots of guys use a (left) foot operated pedal.
In an automotive application, an electric motor(or air / co2 if you have it onboard) is probably better suited to your needs as your feet are already busy and eliminates all the spring pressure nonsense. If there isn't at least 200lbs of pressure on your wing, you don't need a wing, so choose an electric motor accordingly. Also, mechanic advantage with a lever is your friend.

I use this:
https://www.grainger.com/product/DUF...uator-LT-5FTE1
Different attachment points on the arm to adjust speed.
https://www.youtube.com/shorts/fnKAnP5Aavg
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