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Old 05-24-2018, 07:03 AM   #21 (permalink)
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Quote:
Originally Posted by Vman455 View Post
-4.4.8.2: "As indicated in Fig. 4.12, the flow underneath a car spreads outward to the sides. Consequently the wheels are approached at an angle of yaw.... A yawing angle causes the drag of a wheel to increase; Fig. 4.75 gives a typical example. For a yawing angle of 15 degrees the wheel's drag coefficient is more than three times the value for zero yaw."
Wow, thanks - not what I expected at all, and not what I recall reading in the forum before.

As I visualize this, it would seem that the most effective spat would be one that not only covers the front of the wheel but the entire inside length.

That inside length or surface area is 2-4 times that of the width by my estimation.

For the front wheels the inside barrier (linear spat strip) would have to bow/curve and accommodate for steering arc.

Do we have a percentage of air escaping out the sides at 15 degree angle based on the amount originally entering under the front chin spoiler?

My truck has a chin spoiler that is lower than the sides, I assume that increases the amount or ratio of air escaping out of the sides.

On most cars the line of the lowest front barrier is near equal to the sides. That is our most common condition, right?

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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; 05-24-2018 at 07:10 AM..
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Old 05-24-2018, 02:49 PM   #22 (permalink)
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I am just starting to modify my car with skits.

The above descriptions are not fully clear in my mind.

How about an L shaped piece that covers the front of the wheel and the inner side?

The L shape does not need to go the entire length of the wheel well, it could be angled a bit to act as a deflector.
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Old 05-24-2018, 02:56 PM   #23 (permalink)
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Quote:
Originally Posted by kach22i View Post
As I visualize this, it would seem that the most effective spat would be one that not only covers the front of the wheel but the entire inside length.
They're certainly trending that way. Ford Focus, may it rest in peace:



Has a tripartite dam that extends back almost to the centerpoint of the wheel. The C-Max has an identical dam, with the addition of a shaped fairing in front from 2014 on:



Quote:
Originally Posted by freebeard View Post
Can you provide a quote? In the picture at Permalink #15, you can see the front wheel's bottom vortexes passing the rear tire. The dirt carried over-top in the tread is well contained. I'd wondered about those streaks coming off from mid-wheel.
Sorry for the crappy cellphone pic, I couldn't find it anywhere online:

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Old 05-24-2018, 03:55 PM   #24 (permalink)
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thanks, those pictures were helpful.
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Old 05-25-2018, 05:27 AM   #25 (permalink)
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Quote:
Originally Posted by Vman455 View Post
They're certainly trending that way. Ford Focus, may it rest in peace:
The two breaches, especially the one at the corner are odd.

I suppose if they made it continuous there would be more pressure on it.

I'd be tempted to seal those gaps up with some foil tape or rivet a thin strip of aluminum to it. I would not use screws, somehow it will end up in the tire with my luck lately.

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George
Architect, Artist and Designer of Objects

1977 Porsche 911s Targa
1998 Chevy S-10 Pick-Up truck
1989 Scat II HP Hovercraft

Chin Spoiler:
http://forums.pelicanparts.com/off-t...effective.html

Rear Spoiler Pick Up Truck
http://forums.pelicanparts.com/off-t...xperiment.html

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