Meela

About

Continuation of our work on Zola, this time targeting a 3 kg/s LOX flow rate at 40 bar rise with a 5 barA inlet pressure. Completly custom brushless motor design attached to a custom pump, all one integrated assembly. Rated operating speed of 40,000 RPM. We were unable to get it ready in time for Race to Space 2025/26 testing due to an error made with the epoxy during assembly which was not possible to correct in the time avaliable.

I was able to show the back EMF profiles were sinusoid (desired) and of the correct amplitude and even drive the motor to 3,000 RPM using a commercial ESC (capped out due to concerns over improvised mount rigidity).

The assembled motor, with volute casing, inducer and impeller removed.

The machined end caps with ball bearings fitted.

Modifying the printed(!) inducer on my lathe.

We had the 0.35 mm stator laminations laser cut then stacked and bonded them in-house.

Stator hand wound by me. Complete nightmare. Would do it again.

We had to come up with a solder pot one evening...

Mock-up of the stator assembly without external casing.

LOX material compatibility testing of an assembled stator.