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Old 12-06-2016, 08:39 AM   #1
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Default Little aero secrets

Aren't those amazing? I like arrows and rainbows. Did a little mod to see how bad could be and quite pleased to how it turned out.
The first set of pics is flow speed and second set are graphical pressure representation.
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Little aero secrets-tc-full.jpg   Little aero secrets-tc-full-v2.jpg   Little aero secrets-tc-full-press.jpg   Little aero secrets-tc-full-press-b.jpg  
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Old 12-06-2016, 11:26 AM   #2
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I'd be curious see your simulation and comparison of the wing as is versus the wing with a small Gurney Flap (wicker bill). In theory, a Gurney Flap can increase downforce without increasing drag.
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Old 12-06-2016, 11:54 AM   #3
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Originally Posted by J.Filipow View Post
I'd be curious see your simulation and comparison of the wing as is versus the wing with a small Gurney Flap (wicker bill). In theory, a Gurney Flap can increase downforce without increasing drag.
Can't be done. Our wings already have a wicker bill(the part above the curve). But if we cut that part and add a "correctly" shaped WB...Watch this.

I've been testing since yesterday around dinner time! I think I haven't done anything else since! Tested close to 50 configurations, only takes 1 minute to draw the change and another to test.

Added Nascar style WB.

DJ Khaled "anotha one", this one a spoiler feeding a full size wing, cut lower boards and raked body slightly lower.
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Little aero secrets-wicked-bill.jpg   Little aero secrets-nascar.jpg   Little aero secrets-tc-config-x.jpg  
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Old 12-06-2016, 09:40 PM   #4
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Can you share what software you used? I build carbon wings for 1/5 scale gas cars and was curious if this could help in the design?

Thanks

Bruce

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Old 12-07-2016, 01:18 AM   #5
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Originally Posted by belewis01 View Post
Can you share what software you used? I build carbon wings for 1/5 scale gas cars and was curious if this could help in the design?

Thanks

Bruce
Only the profile. Flowsquare 4.0

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Old 12-07-2016, 08:54 AM   #6
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Very cool, got some reading to do.

Thanks
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Old 12-07-2016, 09:04 AM   #7
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Can you test the difference between two wing profiles? Between a tall shallow wing and a short deep wing? One wing is 3mm taller vertically and 3mm shorter horizontally than the other when looking at the side profile.
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Old 12-07-2016, 10:07 AM   #8
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Quote:
Originally Posted by belewis01 View Post
Very cool, got some reading to do.

Thanks
No problem, once the simulation starts I usually use the numbers 9 (for pressure graph) and 4 or 5 to see air velocity. Very helpful.

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Can you test the difference between two wing profiles? Between a tall shallow wing and a short deep wing? One wing is 3mm taller vertically and 3mm shorter horizontally than the other when looking at the side profile.
Let's see if I understood correctly. 2 minutes please.
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Old 12-07-2016, 12:07 PM   #9
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That is quite interesting. With the shorter WB you get a smaller pressure area but the pressure is higher and you also get a smaller low pressure area behind the wing. But why is there a separation between the two pressure areas?

The reason behind the question was that my new body has two cut lines for the wing. Both lines give you a 40mm cord but one has the taller Wicker Bill and the other has a longer horizontal surface.

Thanks for this though, It is neat to see.
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Old 12-07-2016, 12:58 PM   #10
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No problem, just took 5 minutes to do it all!

The separation I think because there's a vortex from the spoiler leading edge/boot lid but it's just me theorizing unfortunately I can't zoom in.

Hope the manufacturer doesn't get mad at me because it's a silhouette of a racing body still used today. *waving white flag screaming fair use*
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Old 12-08-2016, 03:11 PM   #11
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Just as I thought. Having two cuts in the spoiler increase negative pressure behind the third element. Like this:


The problem is using it to our advantage... I can lay down the top part of the spoiler and get rid of the big pressure area, increasing downforce at the rear bumper! Watch the difference.
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Little aero secrets-tc-double-element-wing-pr.jpg   Little aero secrets-tc-double-element-wing.jpg  
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Old 12-08-2016, 04:32 PM   #12
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Am I to understand that in your diagrams, the larger the orange patch, the greater the pressure on the rear wing?

Also noticed that in each diagram your wing starts at the rear of the upper deck (near enough) where we only have a small amount of overhang normally.
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Old 12-08-2016, 05:14 PM   #13
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Quote:
Originally Posted by Skiddins View Post
Am I to understand that in your diagrams, the larger the orange patch, the greater the pressure on the rear wing?

Also noticed that in each diagram your wing starts at the rear of the upper deck (near enough) where we only have a small amount of overhang normally.
Affirmative on the first paragraph, it's on a scale of blue to red, where blue is lower pressure and red is higher. Higher pressures mean trapped air obviously.

That configuration is from J. Groskamp. Non perspective corrected but tried my best from available pics.


And another quick one just to show you.
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Old 12-08-2016, 11:17 PM   #14
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you're playing in some weird places for reynolds numbers. Short chords make wings act strangely...
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Old 12-09-2016, 01:51 AM   #15
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Quote:
Originally Posted by 30Tooth View Post
Affirmative on the first paragraph, it's on a scale of blue to red, where blue is lower pressure and red is higher. Higher pressures mean trapped air obviously.

That configuration is from J. Groskamp. Non perspective corrected but tried my best from available pics.


And another quick one just to show you.
Think the wing should be somewhere inbetween with regards to it's position.
More like this;
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