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Old 06-23-2011, 12:21 PM   #41 (permalink)
COcyclist
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Quote:
Originally Posted by California98Civic View Post
Wouldn't a downward spoiler reduce the wake by taking the attached flow I know is coming down the window and sending it into the wake area? Wouldn't that reduce the wake area? Does that make sense?
If you have time to test this idea I will be following with interest. My armchair QB 2¢ worth is that you won't see much difference because what you have illustrated is well below the "template". When I look at your tuft tests I see evidence of counter-rotating vortexes crashing onto your back glass, not necessarily "attached flow". The tufts at the bottom of the C pillar are flowing out, not inward. There was a thread on here a while back about the New Beetle having attached flow down the back (shown in tuft tests) and a horrible Cd. The angle of the C pillars created huge, spinning vortexes and drag. Aerohead designed the template as the minimum necessary to allow smooth airflow from the top and sides to rejoin and fill in the trailing wake.

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Quote:
Originally Posted by freebeard View Post
The power needed to push an object through a fluid increases as the cube of the velocity. Mechanical friction increases as the square, so increasing speed requires progressively more power.
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