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Old 12-31-2022, 10:36 AM   #621 (permalink)
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Hard to say it's being guided by air flow or if it was just flung or some combination of both. Need to see the patterns when it was being made because the tire fronts are sticking out during turns

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Old 01-01-2023, 07:56 AM   #622 (permalink)
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Quote:
Originally Posted by Phase View Post
...........road salt and red dirt is sticking to is due to low pressure or lift?
I see what you are saying, it is interesting.

1. Salt spray goes everywhere, I would not make too much of it unless it's a striking visual.

2. Red dirt (or "DURT" as a friend of mine puts on drawings) doesn't usually face the side of the car like that.

My guess is that so-called normal wheels suck in some air between the spoke openings to cool the brakes, and this results in higher wheel well pressures that exit out the sides between the wheel opening and outer tire surface thereby pushing airborne particles (dirt) away from the vehicle.

Exceptions on so-called normal cars would be when going though mud and it's no longer air pressure exiting but mud pressure, and that's going to leave a stain.

My conclusion: Airflow and PRESSURE on your car sides is so evenly distributed that anything in the air (disruption of dirt road surface) settles on it because it is NOT pushed away by other forces.

Question is; is that considered "low pressure", pressure that is lower than the surrounding undisturbed air? Which in turn would attract the airborne dirt.

Maybe what we see has something to do with a side Boundary Layer?

https://www.researchgate.net/figure/...fig6_343167605
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http://forums.pelicanparts.com/off-t...xperiment.html

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http://ecomodder.com/forum/showthrea...1-a-19525.html

Last edited by kach22i; 01-01-2023 at 08:06 AM..
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Old 01-01-2023, 01:20 PM   #623 (permalink)
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Inspiration to extend my ioniqs roofline farther and into a mini box cavity like the 1967 mustang. Looks cool and obviously smaller wake. Itís some form of boat tailing
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Old 01-03-2023, 10:07 AM   #624 (permalink)
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10 over

Quote:
Originally Posted by Phase View Post
Well the speed limit between PROVO and and southern utah is 80 and everyone was going 95. I was impeding traffic in the right lane just going 90. Holiday week rush of people blasting it. Going 10 over the limit on a middle of nowhere desert highway is pretty normal
A $ 120 fine according to the Utah Highway Patrol.
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Old 01-03-2023, 10:13 AM   #625 (permalink)
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sticking

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Originally Posted by Phase View Post
Another ski trip with some interesting deposits. Iím assuming the parts the road salt and red dirt is sticking to is due to low pressure or lift?

Front. Middle. Then rear.

Any thoughts or observations or inputs?
The attacking flow is just pushing the liquid rearwards, as long as time-averaged rearwards boundary-layer flow remains attached.
After the flow separates, the random chaos of the turbulence creates the back-soiling.
Keep in mind that, the water is eight-hundred and thirty-three percent more dense than the air, and cannot 'dodge and dive' like the air it's entrained in.
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Old 01-03-2023, 10:35 AM   #626 (permalink)
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Mustang

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Originally Posted by Phase View Post
Inspiration to extend my ioniqs roofline farther and into a mini box cavity like the 1967 mustang. Looks cool and obviously smaller wake. Itís some form of boat tailing
The Mustang's separation line, without spoiler, is at the AST-III elevation.
Your Ioniq, without spoiler is not.
If you extend the top rear, you need to begin at the tearing edge of the OEM spoiler. It's at the AST-III elevation.
The extension should fall away at a 16-degree downslope.
The sides are likely beginning their camber at the rear axle centerline. That curvature should not exceed what the roofline has.
The diffuser angle will depend on 'where' you begin it's upsweep.
You may have the data for the SAAB 9-3 diffuser research. I recommend comparing that to J. Potthoff's, 1982, UNICAR diffuser research.
It would be easy to make a costly mistake.
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Old 01-03-2023, 11:00 AM   #627 (permalink)
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Quote:
Originally Posted by aerohead View Post
The Mustang's separation line, without spoiler, is at the AST-III elevation.
Your Ioniq, without spoiler is not.
If you extend the top rear, you need to begin at the tearing edge of the OEM spoiler. It's at the AST-III elevation.
The extension should fall away at a 16-degree downslope.
The sides are likely beginning their camber at the rear axle centerline. That curvature should not exceed what the roofline has.
The diffuser angle will depend on 'where' you begin it's upsweep.
You may have the data for the SAAB 9-3 diffuser research. I recommend comparing that to J. Potthoff's, 1982, UNICAR diffuser research.
It would be easy to make a costly mistake.
How would a boat tail look on my Ioniq then? Can you make a sketch? What should I do about the spoiler? And flow is attached to the rear glass. Hence no need for a rear wiper like a Prius.
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Old 01-03-2023, 11:53 AM   #628 (permalink)
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?

Quote:
Originally Posted by Phase View Post
How would a boat tail look on my Ioniq then? Can you make a sketch? What should I do about the spoiler? And flow is attached to the rear glass. Hence no need for a rear wiper like a Prius.
1) From the side, any tail extension would fall away rearwards, beginning at 16-degrees, and slowly increasing in curvature, up to a maximum of 22-degrees.
2) If you went out to 12-inches, you'd be at 16.5-degrees.
3) At 24-inches, 18-degrees.
4) ' the-blueprints.com' has a dimensionally-correct image of your car that I've analyzed. Print one of those.
5) Scan the blueprint and place it under the Template, then trace off the elongation contour.
6) Print that, and take it to KINKO's or some place where you can enlarge it to at least 11-inches by 17-inches.
7) This will be your 'blueprint' from which to make scale measurements from.
8) You should buy a stainless steel, 18-inch millimeter rule from an art supply or drafting supply store.
9) And you need a pocket calculator.
--------------------------------------------------------------------------------------
Whatever you build, it needs to begin, where the existing spoiler leaves off.
Just like Mercedes-Benz's IAA and EQXX
-------------------------------------------------------------------------------------
For your 90-mph driving, I'd consider getting a receiver hitch installed, and wait for HARBOR FREIGHT TOOLS to put their lightweight aluminum rear cargo platform on sale. This would make a great foundation on which to construct an easily-removable tail section, which can be firmly attached to the Ioniq without mutilating it.
------------------------------------------------------------------------------------
With 24-inches, your aft-body percentage would rise to 56.7% of overall length.
Car's with this aft-body average around Cd 0.18.
The box-cavity you'd like to build would never help you significantly. And attachment options would be limited.
Sam Sharp bought Three Wheeler's Honda Insight-1 boat tail, and I think he's seeing 80-mpg the way he drives.
It's something to think about.
--------------------------------------------------------------------------------------
As to the rear wiper, it should be submerged within the boundary-layer and if anything, just behave as a tripping device. Removing it might do 'zero' as far as mpg.
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Last edited by aerohead; 01-03-2023 at 11:56 AM.. Reason: add data
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Old 01-03-2023, 01:22 PM   #629 (permalink)
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Quote:
Originally Posted by aerohead View Post
1) From the side, any tail extension would fall away rearwards, beginning at 16-degrees, and slowly increasing in curvature, up to a maximum of 22-degrees.
2) If you went out to 12-inches, you'd be at 16.5-degrees.
3) At 24-inches, 18-degrees.
4) ' the-blueprints.com' has a dimensionally-correct image of your car that I've analyzed. Print one of those.
5) Scan the blueprint and place it under the Template, then trace off the elongation contour.
6) Print that, and take it to KINKO's or some place where you can enlarge it to at least 11-inches by 17-inches.
7) This will be your 'blueprint' from which to make scale measurements from.
8) You should buy a stainless steel, 18-inch millimeter rule from an art supply or drafting supply store.
9) And you need a pocket calculator.
--------------------------------------------------------------------------------------
Whatever you build, it needs to begin, where the existing spoiler leaves off.
Just like Mercedes-Benz's IAA and EQXX
-------------------------------------------------------------------------------------
For your 90-mph driving, I'd consider getting a receiver hitch installed, and wait for HARBOR FREIGHT TOOLS to put their lightweight aluminum rear cargo platform on sale. This would make a great foundation on which to construct an easily-removable tail section, which can be firmly attached to the Ioniq without mutilating it.
------------------------------------------------------------------------------------
With 24-inches, your aft-body percentage would rise to 56.7% of overall length.
Car's with this aft-body average around Cd 0.18.
The box-cavity you'd like to build would never help you significantly. And attachment options would be limited.
Sam Sharp bought Three Wheeler's Honda Insight-1 boat tail, and I think he's seeing 80-mpg the way he drives.
It's something to think about.
--------------------------------------------------------------------------------------
As to the rear wiper, it should be submerged within the boundary-layer and if anything, just behave as a tripping device. Removing it might do 'zero' as far as mpg.
Iím
Saying the Ioniq has no rear wiper. The air flow is firmly attached.

And 2 feet is the range of extension im looking at actually. That would make the car the same length as the sonata.
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Old 01-03-2023, 01:45 PM   #630 (permalink)
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Quote:
And 2 feet is the range of extension im looking at actually.
Finally... at Permalink #629.

Simple or compound curves? Internal storage? Airbrake?

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