Quote:
Originally Posted by euromodder
Weren't they intended for trucks with a big squared off rear face ?
There's be no re-attachment their either.
Going by their website, the airtabs are supposed to create a virtual tail.
At least the boattail and extended Kamm-backs are proven mods. 
So far , no-one here has been able to proof Airtabs / VGs reduce the fuel consumption. |
Way back somewhere we spent a lot of time discussing VGs and I posted an article about an aerospace engineer who developed VGs for automobiles.
The demonstration vehicle was a Honda Accord notchback.Two photos were given with a single long yarn tuft demonstrating re-attachment onto the trunklid rear.
He was borrowing from
'turbulators' used on non-blown/non-suctioned wing flaps at high angle-of-attack.The turbulators offer short field landings at the expense of a constant level flight drag penalty.
On a 18-wheeler,the base pressure of the wake ( pressure drag of the rig ) is governed by the pressure at the separation point.
Since the VG does not alter the separation point it cannot significantly alter the wakes base pressure.
If 'steeper' panels,as Continuum Dynamics has tested with NASA at Ames were installed behind an 18-wheeler VGs would probably help to cheat the air,allowing re-attachment and the formation of locked-vortices,known to help lower drag.
If Airtabs is claiming that their product creates a virtual tail I would love to see them defend that claim in Superior Court.