Quote:
Originally Posted by Grant-53
How does one calculate the finesse ratio of a body with an ovoid cross section and Kamm tail? I learned in technical sales that if I denigrate my competitors I damage my reputation more than theirs. My goal is to get the shell Cd below 0.3 and is stable in cross winds. The primary mounting point is at the bottom of the head tube. I am familiar with sailplane design and construction. I have done coast down tests at 16-17 mph with consistent results on a measured grade.
|
1) Fineness ratio is simply total body length, divided by actual height above the road surface.
2) 'Effective' fineness ratio requires placing the 'vehicle' on top of a mirror (so to speak ), as this is what the atmosphere will 'see;' both the actual structure, plus it's imaginary, mirror-image twin below grade.
3) As to crosswind stability, you'll need to be able to 'come outside the body', using body 'English', shifting your body weight in order to compensate for crosswind loading if you're on two-wheels.
4) Some go to the trike as a solution.
At the IHPVA Annual Speed Trials at Battle Mountain, Nevada, it's quite common to see the top contenders blown into the brush along the highway race course. Stuck inside their composite, Cd 0.11 body shells, there's no way they can transfer their body weight should a gust come along.
