Originally Posted by bdufur (Post 272888)

Based on the tear-drop concept, it does appear that DieselBeetle's kammback design is probably the way for me to go.

Any suggestions from the peanut gallery are appreciated before I get out there with the coroplast and cold beer!:thumbup:

http://ecomodder.com/forum/showthrea...ack-17012.html

http://i29.photobucket.com/albums/c2...f/IMG_0701.jpg

Originally Posted by Sven7 (Post 274168)

;)

http://www.carstyling.ru/resources/c...uto_2000_1.jpg

Originally Posted by Sven7 (Post 274177)

You just might get your wish with the XL1; although it is not a four-seater, it undoubtedly scores much better CdA.

Originally Posted by aerohead (Post 274180)

I certainly hope that they're not just jerkin' our chain with that one.I know that some 'concepts' kinda made it to market,but sometimes were 'castrated' before making it to the showroom.
Placing this car in a James Bond blockbuster might fire the consumer imagination as BMW and other cars have done when seen on the silver screen.

Originally Posted by Sven7 (Post 274147)

Yeah, I honestly doubt that spoiler is doing much actual good. It's so far out of the windstream it's actually just affecting the eddies behind the car. That's why when VW wanted to keep their cars on the road at high speeds they used ones like the Turbo one I posted.

Originally Posted by Sven7 (Post 274211)

I will posit that the sharp edges on the NB only generate very large vortexes in the wake.

Originally Posted by aerohead

Attached-vorticity is a different animal.

The front of a vehicle defines how the atmosphere will be distributed as it passes the vehicles body.

In order to comply with conservation of mass,the windshield and roof cause the air to move at a greater velocity than down the sides of a vehicle,or underneath,due to the greater distance traveled by the air in the same time.
To comply with Daniel Bournouli's (sp?) Theorem,this accelerated flow must exist at a lower pressure than elsewhere around the vehicles body.

If the body designer is competent,the roof curvature,tumblehome, and upper radius of the greenhouse/C-pillar region will be such that when the flow off the roof rejoins the slower flow off the sides,these flows are at comparable velocity and pressure,the they simply continue on in a laminar flow fashion.
If the flows should meet beyond a critical velocity or pressure differential ( delta-V/delta-P) the slower,higher pressure flow will seek out the faster,lower pressure flow,and the two streams will spin up into a vortex as they attempt to blend together.

The vacuum created at the center of the vortex creates tremendous drag,and the kinetic energy required to feed the vortex robs precious kinetic energy from the flow,which,again,can never be converted to useful static pressure,hence the high drag and lower mpg.

If you've ever had a window seat on an airliner you may have seen wingtip vortices form during landing,caused when the higher pressure air below the wing is bleeding over the wingtip into the lower pressure air above,spinning it into a vortex.The pressure drop is extreme enough to create the refrigeration effect which brings the temperature of the water vapor in the airstream below dew-point,creating the clearly visible water fog condensing at the center.

Originally Posted by Frank Lee (Post 274555)

Shoulda just got a Golf huh.