Wanted to start a discussion on these.
The Idea I have is simple, though I am worried about manufacturing.
something like this, but a full 360 sleeve and the fins going around (90 degrees from this picture).
this means tons of airflow, almost now extra drag and cheap. mounted and secured via thermal interface epoxy.
Turbulence can be good to “scrub” into the slots but we need to avoid creating pockets of still air as the cool air rushes overhead. Going helical I think means a longer path for the air through the slots versus rushing over the slots and that might choke off flow through the slots?
IMO having the slots rotated 90° from the image above, simplifying the flow path, would be the most efficient. It would allow easy access to the bottom of the slots and the turbulence behind a board is probably massive anyway.
Hmmm…how much cooling is done by spinning in its own air versus moving forward through “new” air?
I’m only guessing here though based on power electronics cooling and the air flow paths that are used there. Some testing would be easy to do though, either with power resistors epoxied to the sink (and fans to cool) or putting different versions on a motor. Even just using wire ties and thermal paste to hold them on for a quick test could work on a board.
If two halves are used and the sink is spinning the halves should meet up perfectly aligned to prevent creating a set of corners that could accidentally shred things if touched.
Do we have data on how effective this could be, versus cooling by the mounts, etc.? It certainly would;it hurt though and could look incredible.
Safety issues? The sink fins would have to be wide enough to not cut if touched while spinning.
I love the idea and think it’s worth testing. It might only have a small effect on the motors internal temp but the opportunities to make it cool looking are endless.
I love the idea of splitting it into halves to simplify mounting and to allow for different profile front and rear pieces, but a full ring would be more secure.
A lot of epoxies are quite brittle and I think could eventually let go due to vibration. Some way to clamp on the sink(s) would be good. If the sinks are a good fit to the motor can then thermal epoxy isn’t really needed since the layer would be so thin. This would allow the use of “toughened” adhesives, even high temp RTV’s (which can be bought as thermal versions too).
this. @Arzamenable, do you run into thermal throttling issues on your more “spirited” rides? seems like this would be most problematic when running the motors below their optimal speed and above their intended load
why not just size the motors appropriately for the load? Or simply add more motors?
I love “science” too but I think were after the flyshit in the pepper here.