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Old 05-13-2010, 07:48 PM   #159 (permalink)
aerohead
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Quote:
Originally Posted by TechStuf View Post
I understand where you are coming from. No doubt, personal experience is great, but I'm hardly interested in running a jaded gauntlet of those naysayers who will cast aspersion no matter the data... I courteously provided the OP a link to Airtab's site, at which a cursory perusal reveals meaningful results. If NASA's wind tunnel tests aren't enough for others, then my comparatively paltry and subjective data certainly wouldn't be persuasive.



It's not like I'm advocating pulstar plugs here, and as any EcoModder worth his salt already knows, aerodynamic efficiency gains are cumulative. No one addition or reduction is going to do it all. It's also common sense knowledge by now that a flat trailing surface creates a vacuum, which induces drag. By questioning the valid data already produced, that vortex inducers structure trailing edge flow, thereby lessening drag turbulence, one demonstrates ignorance.

Does the rear of a silverado truck end in a point? Obviously not. Would airtabs lessen drag at that location?


Well shucks, apparently that's a hog of a different hue now ain't it.



TS


P.S. My simple suggestion for the maker of the fine silverado aero topper to try airtabs is not responsible for any 'hijacking' of the thread. Topics grow, it's natural. And if by some nefarious chance sprinkling of pixie dust occurs and the OP should see some modest gains by addition of a few cheap airtabs, or his own versions, then I for one, could certainly see cause for a new topic.
Tech,I'm going to throw my two cents in.
The air tab borrows from the turbulator,used in aeronautical work.
During landing of a tricycle landing gear aircraft,and at large angle of attack,the turbulator energizes the boundary layer,allowing function of the ailerons which might otherwise be embedded within turbulence and rendered useless,allowing a crashed airplane.
The turbulator is a constant source of drag but in the toatal energy balance of the entire airplane shows a net benefit to flightworthiness.
The most important thing to consider about the turbulator is that there is something BEHIND it.
If you place turbulators at the back of a vehicle,there is nothing back there for separated flow to re-attach to.
A Mitsubishi Lancer may benefit from tabs,as air will re-attach to the trunklid.
The pickup has no such structure behind it.
The other thing is,that with the new 2010 Lancer,you'll see that Mitsubishi has lost the notchback and has gone to the 'sportback',more like a proper Kamm roofline.Not great but better.
It seems like even they no longer want to play the separation/re-attachment game.
Those little tabs typically require a wind tunnel for sizing,number,and placement.They should be used as a last resort.
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