LIGGGHTS® - User Forum

Hello!

I am using LIGGGHTS FLEXIBLE FIBERS. I made flexible fiber from 50 atoms bonded togeather. I am cutting this fiber by blade and determing loads on blade. I want to make a fiber, which would better describe shape of real fiber so I let atoms overlap, which means I had to turn off pairwise forces. I did that by command neigh modify exclude (with this command I turn off creating list of neigh atoms). But when I use this command forces which were applied by command bond style also disapear.

I am inserting a plate (STL mesh file) into a LIGGGHTS simulation and moving it up and down in a bed of grains. I am trying to output data about the electrostatic forces on the plate but all I seem to be able to dump from LIGGGHTS is the position of the plate. Does anyone know if there is a way to output state data from STL files used in LIGGGHTS simulations?

how to make data file from the VTK file for LIGGGTS?
Explanation-I want to read particle's coordinates and velocities from the VTK file and I want to start new simulation from that VTK file. How to do it?

On a RHEL 9 cluster with VTK installed, why would this seg fault? I just used 'make auto' and OpenMPI 5.0.2.

mpirun -np 4 lmp_auto< in.chute_wear
LIGGGHTS (Version LIGGGHTS-PUBLIC 3.8.0, compiled 2024-02-20-15:56:33 by me, git commit bbd23c8521fe0a4f3f5bfd0d3dc9a7dddd68d90b)
Created orthogonal box = (-0.5 -0.2 -0.4) to (0.1 0.2 0.15)
2 by 1 by 2 MPI processor grid

Reading STL file 'meshes/simple_chute.stl' (mesh processing step 1/3)

Hi, I am having a lot of trouble installing LIGGGHTS on Apple Silicon, can anyone provide more detailed description on installation? Has anyone successfully installed LIGGGHTS on Apple Silicon?

Hello,

I am a new user of LIGGGHTS. I am trying to perform a compression test with a cylinder being pushed into a bed of particles, and plot the force acting upon the cylinder. However, I have noticed that my particles are simply passing through the mesh, and all the forces being outputted are 0. I am not sure what is going on - I have tried to fix this by decreasing the timestep and moving the mesh slower, but nothing has worked. I've attached my input scripts. Does anybody have an idea as to what may be causing this?

Much thanks,
Pearl

neighbor 0.005 bin
neigh_modify delay 0

fix pts1 all particletemplate/sphere 15485867 atom_type 1 density constant ${solid_density} radius constant 0.004
fix pts2 all particletemplate/sphere 32452843 atom_type 1 density constant ${solid_density} radius constant 0.00236
fix pts3 all particletemplate/sphere 32452867 atom_type 1 density constant ${solid_density} radius constant 0.001

How to set optimal value of bin size so that unnecessary force calculation for the neighbor list can be reduced? How this neighbor size is calculated?

Hi there

I'm a new in here. Recently, i have tried to simulate the scratch model with sharp tip and flat surface.
I'm using the LIGGGHTS-INL, which is possible to model continuum such as steel or concrete etc with a bonded particle method.

I can build my own model and explain how it work based on the theory.
But, I want to know how observe the stress within the bond. i think i need to modify some code with related to bond part.

Hello all,
Is it possible to create a lattice with a range of diameter such 2.0:1.0:20.0. And the diameter in the lattice will be randomly distributed. I want to create particle arrangement in a way that a bunch of small particles will covered a big particle. The diameter of the small particle will be different.

variable x0 equal 0.0
variable x1 equal 10
variable y0 equal 0.0
variable y1 equal 10
variable z0 equal 0.0
variable z1 equal 10

variable regx0 equal -0.0001+${x0}
variable regx1 equal 0.0001+${x1}
variable regy0 equal -0.0001+${y0}
variable regy1 equal 0.0001+${y1}
variable regz0 equal -0.0001+${z0}
variable regz1 equal 0.0001+${z1}