Beetle Inspired Aerodynamic Thoughts

[lunarhighway]

perhaps worth bringing up here is the citroen 2cv i somewhat similar car to the beetle (although front engined and originally intended as a true ofroad vehicle)


if you want to race it, you need to make it look like this


when citroen modernised the car's ecterior and created the dyane, it looked like this

but if you want to race it you must turn it into this:


if you google 2cv racing you'll find tons more of these modifications

[aerohead]

Perhaps they could take the 'modded' Citroens out onto the highway and race from gas station to gas station.
Too much fun! Thanks!

[KamperBob]

Thanks for weighing in, Phil. Once again a 3D problem is not well understood by sparse 2D data. Okay, tufts are 2.1 dimensional. Is it any wonder so many people don't understand how invisible air molecules behave around their vehicles as they plow through them? Nope

Cheers
KB

[bnmorgan]

that's why i want to find 3d models for solidworks, or enough measurements to make a reasonable facsimile, to do a little flow work on.

[KamperBob]

Originally Posted by bnmorgan

that's why i want to find 3d models for solidworks, or enough measurements to make a reasonable facsimile, to do a little flow work on.

Bnmorgan, have you seen this thread?
http://ecomodder.com/forum/showthrea...foam-6494.html

Cheers
KB

[bnmorgan]

I haven't but i'm going now.

[AeroModder]

Originally Posted by lunarhighway

Someone should put a Kammback onto a beetle with vertical sides like that. It just might drop the Cd down to .33.

[dmac257]

Originally Posted by Patrick

"In fact, a dimpled golf ball has only about half the drag of a smooth one."

So I don't need to make an aero truck cap.. just put dimples on the surface to lower the drag. My wife has been wanting to beat my car with a hammer for a while

Don

[aerohead]

Originally Posted by AeroModder

Someone should put a Kammback onto a beetle with vertical sides like that. It just might drop the Cd down to .33.

It's funny looking at the race-tuned 2cvs.The Citroen's original Cd is 0.52 and the K-form roof no doubt buys them free horsepower.
One of Dr.Kamm's projects was to modify a Briggs Cunningham coupe for the 1955 LeMans, and it's roofline is well represented in the Citroens.I think he'd be tickled.

[dmac257]

Originally Posted by ChazInMT

Flow looks attached on the New Beetle (don't know a darn thing about the Old Beetle).

I am just trying to learn not criticize one way or another but I get no sense of speed from this picture. It is my understanding from reading in this forum that speed matters. This picture stops action so well there is almost no bluring of the background or the wheels.

My understanding is that at slow speeds there is less compression of the air in front, air moving around the vehicle will be moving slower, the air will remain attached easier, the air will be able to close behind the vehicle easier .. so less resistance and less drag.

Higher speed would mean higher compression of air in front, faster air flow around the vehicle, and air will be unable to combine behind the vehicle fast enough so detaches with drag behind car.

And my question is this: Is the ideal aero template different for different speeds? If so how do you determine the ideal template for a vehicle that will NEVER see 65mph but will normally be driven at 45mph tops?

Don