Hi Seikei,
That video came out of the research group where I performed my PhD. I once recreated it for an outreach activity to middle school children in the US.
I have debated sending these over (input decks), so please do not make me regret it. They are meant to perhaps provide guidance as a base case, and I will not be providing support for them.
Attached are two input decks, in.Fill and in.Shake. The first will fill a cylindrical cavity, while the other will provide the shaking needed to produce the Brazil nut affect. Please see the LAMMPS documentation on commands if you are ever confused.
Provided a snapshot as well of a bisected view of the cylinder after some shaking. Every particle is colored by it’s initial vertical position.
HTH.
in.Shake (1.36 KB)
in.Fill (1.09 KB)