View Single Post
Old 03-22-2011, 09:06 AM   #7 (permalink)
Piwoslaw
aero guerrilla
 
Piwoslaw's Avatar
 
Join Date: Oct 2008
Location: Warsaw, Poland
Posts: 3,753

Svietlana II - '13 Peugeot 308SW e-HDI 6sp
90 day: 58.1 mpg (US)
Thanks: 1,340
Thanked 752 Times in 477 Posts
Quote:
Originally Posted by johnlvs2run View Post
Wouldn't that just slow you down more?

I think a truck doesn't pull the wind forward, it just provides a barrier and lessens the force of the wind.

So having sails would counter the effect of the truck, would catch more of the wind and slow down your car.
The air in the wake of a truck is moving forward relative to the ground, but some of it may be moving forward relative to the truck, i.e. it is moving faster than the truck (relative to the ground). Relative to the truck, a drafting car is not moving, so that small portion of air is moving forward from the car's POV. Of course, this is all happening inside the wake (and/or close to its outer edges), so you have to be very close to catch it. Maybe a small, vertical piece of plexi at the front of the car's hood could barely catch the draft, but any variation in distance from the truck, or a gust of cross wind, could suddenly have that plexi pushing instead of pulling you.

In theory you might see a small gain, but in practice not enough to sacrifice safety. At that distance a tow bar would be much better.
__________________
e·co·mod·ding: the art of turning vehicles into what they should be

What matters is where you're going, not how fast.

"... we humans tend to screw up everything that's good enough as it is...or everything that we're attracted to, we love to go and defile it." - Chris Cornell


[Old] Piwoslaw's Peugeot 307sw modding thread
  Reply With Quote