Convex or flat wheel covers ?

[aerohead]

Originally Posted by Phase

Well to be fair, that car is like a decade old so a lot of newer aero ideas hadn’t been used yet, like air curtains or extended diffusers. The xl1 wheels are more pizza pan shaped which I would say are a hybrid of convex and flat. Not building out and rounded like moon caps. They probably did it for stability and strength of the wheel and to align more with being straight with the body panels. I’m just saying the newer hyper efficient EVs are using more flat covers from this decade

They can build whatever they want, but don't attribute them to lower drag.
The Cd 0.159 Volkswagen One-Liter Car would be instructive.
VolksWagen 1 Litre Concept 2002

[Phase]

Tesla even went from rounded to flat and their range has been increasing. But Tesla isn’t know for low drag mass production cars. What does Elon know about aerodynamics?

[Phase]

Originally Posted by aerohead

They can build whatever they want, but don't attribute them to lower drag.
The Cd 0.159 Volkswagen One-Liter Car would be instructive.
VolksWagen 1 Litre Concept 2002

Huge front wheel arches, no air curtains or rear cavitie, not to mention no diffuser

[aerohead]

Originally Posted by Phase

Huge front wheel arches, no air curtains or rear cavitie, not to mention no diffuser

1) the wheel arches on the XL1 don't appear to be any 'smaller' than for the 2002 VW.
2) BMW was a decade away from inventing the air curtain. And your IONIQ set a land speed record when Hyundai installed convex, MOON wheel covers, and 'CLOSED' the air curtains. You might want to contact them and ask them why.
3) The 2002 VW has more of a proper K- form tail. I'm not sold on the notion that an open cavity has an aerodynamic advantage, compared with a 'closed' tail. Some of the 'cavities' experienced on cars have more to do with taillight and brake light lighting contrast for safety, then for aerodynamics. That's why I've done it.
4) The 2002 car does have a diffuser.

[aerohead]

Originally Posted by Phase

Tesla even went from rounded to flat and their range has been increasing. But Tesla isn’t know for low drag mass production cars. What does Elon know about aerodynamics?

I see them parked at the university every time I eat lunch over there.
I don't recall ever seeing a 'convex' low-drag wheel on any Tesla since 2012.
The wheels aren't even 'directional.'
The same wheel is used on both 'sides' of the car. 'Forwards' & 'Backwards.'
Whereas, the wheels on the Cd 0.187, 1987 Renault Vesta-II, for instance, were dedicated, unidirectionally biased.

[Phase]

Originally Posted by aerohead

1) the wheel arches on the XL1 don't appear to be any 'smaller' than for the 2002 VW.
2) BMW was a decade away from inventing the air curtain. And your IONIQ set a land speed record when Hyundai installed convex, MOON wheel covers, and 'CLOSED' the air curtains. You might want to contact them and ask them why.
3) The 2002 VW has more of a proper K- form tail. I'm not sold on the notion that an open cavity has an aerodynamic advantage, compared with a 'closed' tail. Some of the 'cavities' experienced on cars have more to do with taillight and brake light lighting contrast for safety, then for aerodynamics. That's why I've done it.
4) The 2002 car does have a diffuser.

I actually asked Julian edgar about why Hyundai covered the air curtains for that test and he said that the Hyundai American racing division in charge of the project at the time didn’t understand air curtains and had the old school mentality of taping over every open hole at the time.

As for the moon caps, they probably just went that route because it’s the easier “ plug and play” 100 percent wheel cover versus having to design and make a fully closed on for their record attempt.

[IRONICK]

Originally Posted by Phase

I actually asked Julian edgar about why Hyundai covered the air curtains for that test and he said that the Hyundai American racing division in charge of the project at the time didn’t understand air curtains and had the old school mentality of taping over every open hole

He's kind of right here.

Air curtains have been used on trucks for a very long time. BMW just adapted them to cars. It's nothing new.

That type of wheel covers can be found on the VW Transporter.

[aerohead]

https://ecomodder.com/forum/member-a...vated-view.jpghttps://ecomodder.com/forum/member-a...per-cd0-15.jpghttps://ecomodder.com/forum/member-a...er-profile.jpghttps://ecomodder.com/forum/member-a...aero-truck.jpghttps://ecomodder.com/forum/member-a...-ultralite.jpghttps://ecomodder.com/forum/member-a...oncept-car.jpghttps://ecomodder.com/forum/member-a...lt-vesta-2.jpghttps://ecomodder.com/forum/member-a...oma-cd0-31.jpghttps://ecomodder.com/forum/member-a...-pickup-gm.jpgI dove the BOLT, IONIQ-5, and IONIQ-6 over Thanksgiving, and had previously driven the Model S 100D.
All can be driven one-pedal, and I didn't need the 'brakes' at all for these cars.
Which suggests that, with BEVs at least, there would rarely be a 'need' for wheel ventilation for brake cooling, as the brakes themselves aren't necessarily needed.
The mass of rotors and drums are supposed to be engineered to store all the kinetic energy ( heat ) of a panic stop, with a fully-loaded vehicle at top speed, without warpage, or compromised stopping power.
For ICE vehicles and hybrids, wheel ventilation needs would require a different calculus.
Just an observation.
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[Piotrsko]

You also dont drive BEV's down pike's peak like a racer. If you used the brakes like a non regen vehicle, they're gonna overheat just the same as a gasser. The energy dissipated either goes into the motor or the wheel or both, but it's still going somewhere and it still makes things hot.

[Phase]

Originally Posted by Piotrsko

You also dont drive BEV's down pike's peak like a racer. If you used the brakes like a non regen vehicle, they're gonna overheat just the same as a gasser. The energy dissipated either goes into the motor or the wheel or both, but it's still going somewhere and it still makes things hot.

I fully either close my wheels for long highway trips where I’m just steady state traveling and never braking, or close them all the way with city driving in winter. Brakes aren’t gonna get hot when doing regen hybrid hypermile braking in 45 degree weather