LIGGGHTS® - User Forum

Hello,

I want to insert particles in cad files. after that compress it and rotate it. When I'm trying to execute the program. particles are falling down to cad files. .Plate is not rotating. Can anyone help me . Please find the code below:

### Initialization

# Preliminaries
soft_particles yes
units cgs
atom_style granular
boundary f f f
atom_modify map array sort 10000 2.0
neigh_modify delay 0 every 1 check yes page 500000 one 50000
newton off
communicate single vel yes
processors * * *

When using the "gran surface multicontact" my simulation crashes for no apparent reason and Liggghts does not output an error.
I'm using the latest Liggghts that I built myself on Windows with MSMPI and vtk

When running with a single processor, the visual C++ error popup says: "cannot dereference end list iterator"
An image of the error is attached.

I've also attached my script as a reference

I’m working for semester project in University. My task is to calculate the friction between rubber block and soil. My program is running but im not able to find output which required.

My idea is to insert particles in soil plate, compress it with top plate and rotate the soil plate against rubber sample.

1. Particles are inserted but when .stl file is rotating, particles are not moving along it.
2. I used ave\time to calculate the momentum. I thought to calculate friction from it using simple phyics law. But I didnt find where I can find ouput of the syntax.

Please help me.

How to make shared libraries for python on windows 10 ?

Plz see attached triaxial simulation

Problem : Particle are not compressing during the simulation.

Any COMMENT/help will be highly appreciated! Thanks

Hello,

I am trying to model a packed bed situation with a bottom wall of temperature 1000K and allow conduction through the bed. (This would involve inter-particle conduction as well).

I have been trying to add in a fix heat/gran/conduction value to allow for particle-wall conduction with no luck (no heat transfer happens at all). Can someone help me out? I am quite new to LIGGGHTS. I have attached my base code which has a heat source and sink which I do not want either - just conduction due to the heated wall.

Thanks

Hello everybody,

in LAMMPS documentation it is recommendet to use colloid and yukawa/colloid for DLVO potential.
I'm trying to use DLVO in LIGGGHTS (CFDEMcoupling) and now I stuck with the equations in colloid.
In LIGGGHTS only colloides are calculated, solvent is done by continuum. Does this mean the equations for colloid-solvent and solvent-solvent are not considered? Or is it computed with information transfered in the coupling?
Is there any hint, documentation or literature?

Thank you.

Henrik

Hi All,

I have a small question. Is the output results of LIGGGHTS simulation with same conditions differ? If say three or so same cases, same set-up, same conditions and same configuration are run, will there be any deviation?

Thank you.

I want to create cylinder(at coordinates 0, y,0) of radius 12.25 cm and o.74 cm height for region to insert particles. but its not creating at exact position.

Please help me. Code below

### Initialization

# Preliminaries
soft_particles yes
units cgs
atom_style sphere
boundary p p p
newton off
communicate single vel yes

# Domain
region reg block -1 1 -1 1 -1 1 units box
create_box 3 reg

### Setup

Hello everyone,

Right now I conducting a undrained triaxial test. The top and bottom walls are moving closer to compress the particles by "fix move/mesh" command and then the position of the side walls can be calculated. But I am confused on how to control the position of the side wall. I searched in the forum and found that in the old version of LIGGGHTS, the position of side walls can be controlled by "fix move/mesh/gran variable" command, but now this command doesn't exist anymore. Does anyone know how to control the side walls?

Thank you so much!