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Old 01-21-2015, 03:11 AM   #12 (permalink)
Vekke
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Location: Kitee (Finland)
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Quote:
Originally Posted by aerohead View Post
*Wheelhouse drag has to do with the volume of the wheelhouse in which the wheel/tire occupies.
*You could calculate the difference in the overall 'void' attributed to the addition of the wheel covers.
*You'd want to test for the entire wheel-flop range of motion to ensure that nothing collides with the wheel arch.
*I'm unsure of what the flow over the wheel will do when the cover protrudes so far from the wheel.Technically this is a no-no aerodynamically.Some of the air will try and ride the wall of the cylindrical covers,while a portion will attempt to spill over the outer edge.Since it's spinning,the 'trailing edge' cannot be boat tailed,giving the wheel a larger overall frontal area.
*Un-skirted,having the outer face of the wheel even with the body is good only if the tire is even too.
*Would not the articulated skirts as on AEROCIVIC not be easier to deal with?
There are few reasons why this in better in my opinion and one them are looks. I know I can build nice lookin hinged front skirts, but they would still look not cool IMO. At least I will test these in action.

This car had 225/60R16 and now I will propably have 195/65R15. There happens to be that 42mm diameter difference to that original tire diameter, so the cover is same size as oem tire so no problems should occur.


I am not understanding the bigger frontal area as its in the wheel housing and only will come flush to cars outer edge?

I do understand the wheel rotating and riding that cover cylindrical wall, but it migth be possible that air somehow stop with the cover so it wont leave the cover.
Block the inside of the cover edge etc


http://ltces.dem.ist.utl.pt/lxlaser/...apers/15_1.pdf


Here I dont understand the Scx Scale? Its related to wetted area which means the frontal area or the volume. Anyway in that study best and worst case delta cd was about 5%
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Last edited by Vekke; 01-21-2015 at 03:44 AM..
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