Quote:
Originally Posted by serialk11r
The thing is I've seen on the internet "active brake cooling" devices that are just small ducts. A wheel is rather large, even if it's not shaped ideally for pushing air, it is one big fan. I think at 60mph your wheels are spinning around 1000rpm or so (this might be completely wrong btw, I haven't bothered to think about it), which is actually pretty good. A 120mm low speed case fan spinning at 1200rpm pushes a pretty good amount of air. If you use the whole rim as a fan (albeit a not so ideally shaped fan) you can likely provide more cooling than a typical duct.
The actual power it takes to do this is pretty small, on the order of 10s or hundreds of watts most likely. Think a cooling fan for your house (do people in America even use them? lol). The really fat ones are like 300W, but they spin rather fast and have crazy huge blades. Also remember that most rims aren't very aerodynamic anyways and have some sort of loss to aerodynamic drag via spinning anyways. We could go further, use a centrifugal type blower fan and a housing that threads through the hub, and use it to directly enhance airflow around the side of the car but that would be rather complicated and mostly pointless.
And you don't need left and right wheels, they all blow outward.
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I believe this was tried in the 70s and 80s on certain racing cars but I don't know if it was for brake cooling, or to pull air out of underneath for downforce, or why it stopped. Maybe they could try again with better computer designed spokes/fan blades? (But I don't know if I would go for the looks...)