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[CliveFx]

Hello all,
I am the founder of a small NewSpace company Acceleren Kinetics, and I am doing experiments into the use of metalized waxes for hybrid rocket fuels. I have already tested one engine ignition system using an aluminum/paraffin wax combination (40% German Black aluminum powder by weight), but it was a small trial engine with a grain diameter of 0.75 inches.
see that here:


As my next vehicle has a grain diameter closer to 2.5 inches, I need to figure out a way to ensure a homogeneous distribution of aluminum particles in the fuel grain. In addition, the grain will have to be either spin cast or vacuum cast to ensure a voidless grain. My concern is that spincasting (rotating the grain along it's long axis) will encourage the aluminum particles to the outside of the grain.
There are two ways to tackle this, one way being purely mechanical, and the other being chemical.
The aluminum powder is 5000 mesh, pyrotechnic aluminum powder
The wax is standard fully refined paraffin OR monocrystaline paraffin, depending on which one fares better on the test stand.
Questions:

1. What mechanical mixing/blending machines could help ensure a good mix? I know mixing kettles are a good stand, but what about three roller mills and other devices? I am new to chemE so I don't know what the options are

2. Do emulsifiers help slurrys or only emulsions? i have ordered samples of Ganex-220v and 660 as they were noted in a few patents as being used in this application for the production of explosives.

3. Would a very slow cooling of the grain help ensure a good cast? I am considering running nichrome wires through larger grains, heating the outside and inside with hot nitrogen and slowly bringing the whole grain temp down at once so the whole thing cures at the same rate rather than outside-in

A even distribution of aluminum powder in a voidless grain is imperative. The grain will be under up to 5gs of loading from acceleration alone, and be held in an 800 PSI chamber. The aluminum is added to create a fuel with a higher energy density, therefore smaller grain diameter, therefore smaller vehicle diameter, therefore less atmospheric drag.

Thanks for any help!