Quote:
Originally Posted by donee
Yep, I have read the Mitsubishi paper, and their goal was to make their wing work better.
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True - and that raises a good point: The 0.006 drag reduction they saw was
after they got the wing working better (ie. probably increasing drag). Perhaps the net change
without the wing might be more than 0.006.
I still don't doubt the end-of-roof placement of the VG's though. EG:
Renault wasn't trying to shepherd airflow toward a wing; they only wanted to reduce drag by minimizing the size of the trailing wake - ie. moving the separation point further down the back glass.
EDIT: and the boundary thickness at the end of the roof is also mentioned in the Mitsu paper: 30 mm.
There's no flow separation at the top of the windshield on modern cars (some Jeeps, SUVs with more vertical glass notwithstanding), so VG's there won't help. Describing the flow as being "thrown upward" doesn't match what a simple photo shows:
