Something about air... I forget.

[Xist]

Many years ago I read a Popular Science article about making planes and trucks more aerodynamic by compressing air and releasing it in strategic locations. The article sounded like the theory was successfully tested, although I have not heard of it since, and would not have any idea how to track down the article. I looked through the first hundred Google results for "plane truck compressed air Popular Science" and, of course, it was a waste of my time.

I was just thinking though, if a low-pressure zone, like the bottom of your windshield, increases drag, and so does a high-pressure zone that pretend Ecomodders have on their side mirrors, would there be any gain by piping air from the top of the hood to around the mirrors. How much of the wake could you fill?

These are the things on my mind when I try studying for finals...

[gone-ot]

...NASA tried using pin-holes along portions of a wing and forced air thru them.

[kach22i]

Originally Posted by Old Tele man

...NASA tried using pin-holes along portions of a wing and forced air thru them.

Yes, see post #8 here:
Fan & Propeller shapes: Sickle and Curved

EDIT: direct NASA link...............
http://www.grc.nasa.gov/WWW/RT/RT200...unningham.html

[some_other_dave]

I hadn't seen the propeller blade work. I'd seen write-ups on the wings. IIRC, they worked well at keeping the flow over the wings laminar, so there was less lift-induced drag. But they took power to run the compressor, and the grid of very small holes needed were very difficult to keep clean enough to work.

There may have been unpleasant effects at moderate angles of attack as well? I don't quite remember.

The issue of the holes getting plugged was big enough that they abandoned that line of research after a while.

There was something also done with rotor blades for a helicopter? I don't think that one made it off the drawing board, though.

-soD

[freebeard]

No reference, but I read a detailed history of British aeronautical research in the 1930s. They experimented with perforated and foamed metal surfaces and rejected them for the reasons SoD stated.They settled for blown flaps.

To answer the question: I don't see piping under-hood air to the mirrors without increasing the frontal area. If you have a positive displacement cooling fan, or air brakes, you could pipe compressed air up the stem of the mirror and have Coanda nozzles around the mirror itself.


kach22i -- interesting thread

[Xist]

So, cut off the mirrors with a light saber and use the Force?

[radioranger]

I'll throw another twist into this , isnt hot air more slippery than cold air , so I'm thinking hot air ducting or even darker surfaces where the air drag is highest, sun induced aero dynamics, LOL

[radioranger]

Like i tell the kids sometimes, that ideas so crazy It..just,,might,,,Work !!

[jeff88]

Originally Posted by Xist

So, cut off the mirrors with a light saber and use the Force?

I think I am going to put this quote in my sig, so all can see! Hahaha!

I remember reading a thread here about somebody having an idea to pump out sound to counteract the air around the car. Something about acoustic resonance IIRC. That might be easier to do then trying to pump air to where you want it. I'll try to remember to find the thread when I get home, unless somebody beats me to it.

[freebeard]

Hope you're home safe.

http://ecomodder.com/forum/showthrea...ion-24764.html?