Fins in hub motor holes for cooling

I want to find a shape that can fit in these 6 air holes in the motor's rotor and the air will exit out of holes on the other side of the motor that aren't spinning.
The purple flange holds the wheel and there are small recesses in the steel u can see for screen.

Is there an ideal shape fin or something that would fit in this 3mm thick hole. Or the fin could come further in a bit. Or maybe I could add a lump of material on the side of the hole and create a vacuum?

If I can find a shape I could 3D print it and then make a mold and pour it in whatever material and glue it in or on

Its a older thread now but I believe it would work with a good design

Im thinking of louvered type fins like those use for louvered hoods

Not sure how this would work in practice but my theory is the louvers on one side of the hub would go in one direction the other side would have them in the other direction so the air cycled threw by wheel rotation where the faster the speed is the more air it passes.

I notice the axle passes a lot of heat to the forks , maybe something can be done to cool threw the axle better. All i can think of is to pump air in threw the axle hole using a dc fish aerator. It may well do nothing who knows it might help ..

Trying to "scoop" air into the hole will do almost nothing as the effective fan blade is too small. Instead and very effective with outrunners is a straight radial centrifugal fan blade like used on car alternators. There are even some sold for RC outrunners. The way it works is the centrifugal fan throws air off of the blade tips creating a low pressure region behind the blade. Air will then be sucked through the motor from the other side and out the holes on the end of the rotor can. I've used this approach with my hubmotors and they run much cooler than the spendy results of the latest fad of ferrofluid and hubsinks.

There should be a kit to mod DD hubs with the blades . It makes good sense that its the key to hub motor cooling. Alternators have been using the design for what 75 years now