What do tricks and golf balls have in common? Surface textures designed to help fill the void behind each in order to move more efficiently, or farther in the case of the latter. These vortex generators produced swirls in the air that help fill that gap that would otherwise create suction at the rear.
The treatment below is rather more of a quandary, but sidewinds squeeze into the gap between cab and trailer creating drag, and I'm guessing this is less of an issue if there's an 'air curtain' between the two made of high-energy swirls of the same?
All a bit of a green box-ticking exercise in view of the fact a fifth of trucks on roads are running empty, but beats doing nothing at all.
