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Old 02-11-2012, 05:13 PM   #33 (permalink)
aerohead
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bean

Quote:
Originally Posted by NeilBlanchard View Post
What is the (approximate) Cd of the "bean" model in in photo 44 (in the first group of 5 galleries)? That arch is sure ugly, and it is counterintuitive. It seems like they were trying to raise the vehicle to let the air flow more freely under the car, but then still trying to "fair" the wheels...
Wow Neil,sorry! Today I'm just now catching your question.
The CNR 'banana' car started as a scale model in 1976.In ground proximity with a 'full' tail' the body scored Cd 0.16.
When they chopped the tail off to the length of the 1978 full-scale model,the Cd increased to only Cd 0.161.
In 1978,when they added wheels to the body,the Cd jumped to 0.35!
Morelli worked to fair the tire/wheel assembly,finally getting the Cd of the full-scale mockup back down to around 0.201,with cooling system,features drag,mirrors,wipers.
The arched,crushed-Omega,high rear,reflex-camber body is a strategy for high crosswind stability and is similar to a von Mises wing section.
In comparison to the 1980 VW 2000 concept,with production-ready Cd 0.25,the 'banana' has some advantages and I think this is why Aptera leaned towards it.
Sorry for the late response.
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