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Old 02-13-2018, 02:23 AM   #25 (permalink)
Angel And The Wolf
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Quote:
Originally Posted by freebeard View Post
They're fat-tired open-wheel cars. The high drag comes from the tacked on wings. The underbody does contribute downforce. It does it by expediting the airflow through a closed plenum with tunnels and induced vortexes. I don't think that adds drag, but I've been wrong before, once.

I talked above about a 'pontoons enclosing the wheels'. More specifically look at the spats on the Template as Xist showed at Permalink #16 (that you keep cutting off). And look at basjoos' Aerocivic:

Aerocivic - how to drop your Cd from 0.31 to 0.17

https://www.aerocivic.com/

I notice the Aerocivic has the same high tail that I originally started with. Someone told me that I needed to keep the bottom at 2.8 degrees, or did I misunderstand? Very possible.

Quote:
Originally Posted by freebeard View Post
It has double-walled side skirts flushed to the inner and outer walls of the tires, 'catamaran-style'. It has zero break-over angle
I don't know what a breakover angle is.(?)

Quote:
Originally Posted by freebeard View Post
but I think the skirts are conveyor belt material. Notice also the wedged out nose and high boat tail. They work together.

Here's my own theory on how to terminate a Template shape (this one is squircular):



It is an half-bellhorn diffuser that couples a flat bottom to the truncated tail.
Interesting. Don't the lower sides of the bellhorn drag in dips?

Quote:
Originally Posted by freebeard View Post
It's all the same from approximately 25mph to approximately 250mph. More benefit going faster.
So, do you favor the flat 2.8 degree, or the profile curve for the bottom plate of the boatail?
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