Quote:
Originally Posted by Scrappydoo
No, my point was that if you want to improve heat loss from the disks then why not remove the shrouds?
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I thought about this a lot more and did some napkin math and I'm even more confused now. let me illustrate some points and make no clear conclusion.
1. the rotors obviously pump air.
2. the rotors pump a lot of air. doing napkin math, the ducts are about half the size they need to be in order to provide enough air to the rotors that there would be positive pressure before the entrance to the rotor at 80mph.
3. when the rotor is pumping, and the shroud is in place, the rotor pulls air from the area that is shrouded. that means it pulls air over the surface of the rotor, then pumps it back out through the inside. this should be substantially more air flow / cooler air over the back rotor surface than it would see simply spinning by itself in standing air that wasn't being pumped.
4. if you remove the shroud, it should improve the rotor's pumping effect, which should help cool the inside of the rotor a lot. but you lose some effect of the pump on cooling the back surface of the rotor. however you dramatically increase the back surface of the rotor's radiative cooling capability. another side effect of going without the shroud is that the air going into the center of the rotor is cooler.
5. because of 3 and 4, running without a shroud will cause a higher heat differental in the back rotor surface, but should cool the front rotor plate better and give more even cooling on one side of the rotor versus the other.
there might be some impact on rotor life regarding heat differential... it might be that one way is better than the other. i suspect cooling from only the center would be more prone to cracking but i'm not entirely sure if the difference between one side of the rotor to the other would really be that high that cooling only on the inside and decreasing cooling on the rotor surface would have much of an impact on cracking...
so now i have no idea if the shroud is beneficial or not. at least it helps keep the dust down?
starting to lean toward the idea that it should be minimal shrouding.