Quote:
Originally Posted by mikesheiman
Granted, something like having a virtually non-existent wheel well gap on the inside of the front wheel for a standard shaped car (and almost no air gathering behind the front wheel) may be ideal, but
A) How can you fabricate something like that, that eliminates almost all air entering behind the front wheel, around brake lines, the steering rod, the suspension, and other parts?
B) For what air does gather right behind the front wheel, is it actually better to just let it sit there vs. form a vent to drain any air pressure behind the front tire out the side and thus add pressure behind the front tire's low pressure area?
I understand that it's ideal to fair the entire tire separately from the rest of the car body ALA that salt flat car design (option "C"?), but being able to custom-fabricate something like that is honestly beyond me.
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A) we'd have to take each car on a case-specific basis.And you wouldn't attempt these details until the rest of the car was 'done.' And you'd have to be REALLY motivated to take this on (bordering on obsession).The lowest drag concepts maintain some degree of the hour-glass openings to allow wheel flop at the front,so it may not be necessary to engineer for closing all of that off.Simulation of a totally-sealed belly in a wind tunnel would indicate if this fruit was worth going after.Tested models from the past indicate that Cd 0.13 is possible without wheel fairings,if this area is sealed.Today's cars use fairings to get the air to 'jump' the opening,then reattach downstream of the opening.
B) Ford's research with the Probe-IV indicated that there's no benefit doing anything behind the front wheels.Not so with the rears.This makes the front a little easier.
For the return trip to DARKO,I'll attempt to mimic a fully-streamlined belly,including full wheel fairings,just to isolate the effect of the hour-glass area.Measurements will tell me if it's worth the effort to pursue a 'streetable' version of the mods.
Get you car down to Cd 0.16,then see if you want to go further.