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Old 11-09-2008, 12:52 PM   #40 (permalink)
trebuchet03
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Join Date: Dec 2007
Location: Bay Area
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The Miata - '01 Mazda MX-5 Miata
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Quote:
Originally Posted by NeilBlanchard View Post
Hi,

Since zigzag tape is so thin, it cannot help reattach turbulent air. The pictures of the zigzag tape in the wind tunnel have it in the high pressure air on the leading part of the wing, and it helps create a slip layer near the surface.

It can't pull turbulent air in from a distance away.
That's the thing about any sort off VG - which includes zigzag tape, dimples, etc... The whole theory behind it never involves turning turbulent flow into attached flow - it's taking turbulent energy and transferring a bit into flow about to detach.

Furthermore, I'm not convinced comparing a sailplane to a car is of any use. The ASK 21 sailplane has a max speed (where this tape would have most effect) of 175mph (if you can find minimums, that'd be great) and is a streamlined body to begin with. Maybe the lower pressure offsets the velocity discrepancy - I'll have to do a quick calc a bit later
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