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Old 11-17-2008, 12:07 AM   #52 (permalink)
trebuchet03
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Join Date: Dec 2007
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Quote:
Originally Posted by Deezler View Post
Most advice I've seen for VG placement on a passenger car is for them to be about 100 mm in front of the start of the major rear angle.
That advice comes from ignorant users.... I don't mean the word ignorant as an insult, however

If you're going to re-energize the boundary layer - it needs to be placed in the transitional zone. Essentially, where the BL starts becoming too thick, on the verge of being called turbulent. Where is this zone, physically? You're not going to know by just looking at a car The only way to know is by either physically testing, which is expensive and time consuming... Or analytically testing (cfd).

The reason they tell you 100mm in front is because that's what Mitsubishi did - read up here: http://www.mitsubishi-motors.com/cor...004/16E_03.pdf - it's a pdf.

From the paper






If your car is a Mtisubishi Lancer - 100mm is correct.... Otherwise, it depends on the car, where flow starts to separate etc.

For example - the Fusion 999.... I don't necessarily see why it should be added....
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