Rounded Belly Pan
 

Was thinking about belly pans and was wondering if it would make a more efficient belly pan to curve it slightly to simulate the tear drop.

What do you think?

If it can rise toward the back, then that is good. Wheel strakes on the back wheels in particular would be also very good.

Luigi Colani got there first. His C-Form ran at Bonneville in the 1970's.
http://i.imgur.com/J6Ttn.jpg

hello,

a flat belly is better. Also difusors are bad for a good cw

That Colani looks like upside-down WINGS...for downward force?

Jack-Lee -- For why? Also [Citation needed].

Old Tele man -- Colani's inspiration was the Water Strider. The rake and asymmetrical airfoil was for traction on the salt. But the Human Powered Vehicles settled on the same solution, don't even try to keep the air out—compress and decompress it smoothly and put spats on the wheels.

Colani did it in the 70s. I've been thinking of a Schwimmwagen body with a Class 5 offroad stance, if you know what I mean. And a blown Lexan bubble top Ed Roth top. And a single trolling rod antenna with three little Jetson disks on it.

You could do that front suspension with a tube axle and hair-pins. Invert the axle so it's up in stagnant air and clip that U-shaped fender to the hair-pins. They would pivot at the bottom of the windshield.

Too much rise on the underside and there will be drag; just like on every other "face" of the car. The underside is more critical because the ground itself limits how quickly the air can flow back into the space "left behind" by the moving car.

I think that Colani is a high drag design.

Looks to me like there are wheels and such obstructing the flow "back in" under the Colani car. Wonder what the real Cd of it is.

I looked around a bit but couldn't turn up anything. The text in this picture is the patent form, but it shows the influence it had on contemporary race cars:
http://i.imgur.com/Pthpt.jpg
My recollection is 0.17 or 0.18 but [citation needed].

NeilBlanchard -- Maybe. The road is moving with the air, not the car. I'm not sure if that supports your point or mine. :confused:

Hello,

i earned this exprience by build velomobiles.
the quickest VMs had all a flat belly.
Other geometries gain the airflow under the bottom -> more drag
Diffusor-> gains the airflowspeed -> windresistence gains ³

But a few VMs are constructed with rounded belly
http://www.bhpc.org.uk/Data/Sites/1/...Miles/q/q1.jpg

Greetings,
Patrick