Hello Everyone,
I have recently started to use LIGGGHTS and loving it so far. I am trying to generate a steel ball of diameter 30 mm inside a defined spherical region, and I want to generate the ball at the center of the region but it is randomly being generated elsewhere. So I want to know if there is any fix or way to generate it at the center.
BT2786 | Mon, 04/21/2025 - 14:31
Place a Single Particle at the Center of a Spherical Region
Hi Sarwar,
Great to hear you're getting into LIGGGHTS!
To place a steel ball exactly at the center of a spherical region, avoid using fix pour (which is random) and instead manually define the particle position:
1
Define the spherical region (example, centered at origin):
lammps
region sphere_region sphere 0.0 0.0 0.0 0.015 units box
2
Create a lattice (any type, just for syntax):
lammps
lattice sc 1.0
3
Place the particle manually at the center:
lammps
create_atoms 1 single 0.0 0.0 0.0
Also, make sure your particle properties (e.g., diameter 30 mm) are correctly set via fix property/global.
We’ve handled similar setups in DEM-CFD coupling projects—happy to help if you’re expanding into multiphase flow or large-scale simulations.
Daniel Tan
https://Broadtechengineering.com