[geeks] Drag software

[Michael Dombrowski]

My little brother is in Boy Scouts and the Pinewood Derby is coming 
up soon. Naturally he wants to win, and I think it'd be cool if we 
could design the car in the computer and do some simulations then 
build it. The CAD software I know best, Cadkey 19, does do drag 
calculations I'm pretty sure but I'd like a better solution, like 
software that shows me exactly where I'm encountering air resistance. 
I believe I want some sort of CFD package to do this. Am I correct in 
this assumption? Are there free packages out there to do this? I've 
found a couple resources like:
http://capella.colorado.edu/~laney/software.htm
but my inexperience in the field is limiting me. My needs are very, 
very simple. The models are simple, they will move in one direction 
in standard air pressure, etc. Idealy I'd like to take my Cadkey 
model, convert it to dxf or whatever file format is needed, run a 
program on it and get a colored model out that I can rotate etc, or a 
series of image files.

Also, are there any good free Unix cad programs? BRL-
CAD(http://ftp.arl.mil/brlcad/) looks like it might work but looks 
older.

Mike