View Single Post
Old 09-08-2008, 01:20 PM   #2 (permalink)
Funny
Master EcoModder
 
Funny's Avatar
 
Join Date: Apr 2008
Location: Massachusetts
Posts: 409

Eco-Fit - '13 Honda Fit Base
90 day: 37.06 mpg (US)
Thanks: 30
Thanked 18 Times in 18 Posts
Quote:
Originally Posted by lunarhighway View Post
I'm inclined to think a spoiler with a sawtooth trailing edge might have advantages over a straight one.

here's how i arrived at the idea.

first of all vortex generators have the ability to reduce drag, while their effectiveness is debatable in some applications their fuctioning is quite well understood.
now when i compared vortex a vortex generator with a naca intake, the first thing you notice is they're very similar in shape, in fact a naca intake also uses vortexes to draw air into it's orifice, so basically a naca intake is an embedded vortex generator that draws air from outside in.

so what if we where to use a series of naca ducts in a lip spoiler. likely the naca intakes would draw air from the top of the lip to the bottom of it!
all of this would be a low drag affair, and no additional frontal area is generated.

one could simplify this setup by cutting of the rear of the naca duct leaving a trailing edges with a curvy sawtooth pattern, wich might even be further simplified to just real sawtooth, as are used on turbulator tape for example.

the whole idea starts to make even more sense, when you realize humpback whales have fins which rounded sawtooth like protrusions at the end, which in turn have been copied to design low drag blades for huge wind turbines.

so what do people with a better understanding of aerodynamics think? am i drawing the wrong conclusions or is there something there?
Not to push you in the wrong direction, because I think you are onto something here, but these Austrian people design computer case fans with notches in them to keep them quiet and push more air:

Noctua Fans

Also this is (was a while ago anyway) a topic of discussion in this thread:

Whale Tubercles
This may assist in your venture. Good luck and keep us informed.
__________________
American by right
Ecomodder by choice
Hypermiler by necessity


Last edited by Funny; 09-08-2008 at 01:27 PM.. Reason: To add post from other thread.
  Reply With Quote