LIGGGHTS® - User Forum

How to use DLVO potential in LIGGGHTS?

I have successfully compiled the colloid package from LAMMPS in LIGGGHTS, but I encountered some problems when I use it.

The error message:
ERROR on proc 0: Overlapping large/large in pair colloid (../pair_colloid.cpp:187)
ERROR on proc 4: Overlapping large/large in pair colloid (../pair_colloid.cpp:187)

Thanks.
Xie

I would be really happy that any of you share a triaxial code with me as I am beginner in this field.
I have already wrote this code :

#####################################################################Triaxial Test######################################################################

#################################################################### Granular model ####################################################################

atom_style granular

atom_modify map array

boundary m m m

newton off

communicate single vel yes

Q1. Does liggghts control maximum normal overlap between particles or is there no limit to maximum normal overlap?

Q2. How is temperature related to kinetic energy of each particle? What will happen if temperature is not maintained constant for simple granular flows?

Q3. How to create initial lattice of particles (specifically, how to increase the packing fraction of initial lattice of particles?)

I'll be grateful if I can get responses as soon as possible as I've to add these things to my master's thesis.

Thank you!

Hello!
I need to calculate the stress due to deformation of two bodies. I have been using the compute/stress command to do so. On comparing with the forces which i calculated manually for a given deformation, I realised that the stress values that i got from LIGGGHTS is actually equal to the force * overlap.
I wanted to know if indeed the compute stress/atom command is storing the work done due to deformation. If so, which files can I refer to where the calculation is being done?

Hello LIGGGHTS forum, I really appreciate your help.
I have been trying to do a simple simulation. Recently I noticed that more particles are created when iteration is increase. I actually need only one particle in my dump file. I have included my script and dump.data file here with few questions.
Could you kindly help me?

Scripts:
# Initialize

atom_style granular
atom_modify map array
###########################################################################################
#Describe boundary

Hi,

Since I am new to DEM, I have a very basic question. Is there a way to fill a geometry with particles by using insert/pack? Maybe define the Geometry as a Region in some way?

Any help appreciated. Thanks. Regards,
Leandro

Hello
I am relatively new to LIGGGHTS-flexible fibers, and I don't understand the effect of neighbor settings quite well. My model has particles of diameter 30e-6 m. Simulation box is cubic with edge of 1000 * particle dia.

When I run with following neighbor settings on my PC:, it runs fine
neighbor 0.001 bin
neigh_modify delay 0 one 5000

Hello!
I have been trying to use the gaussian curvature for the force calculations between two superquadric particles. To do so , I have used the command :

pair_style gran model hertz/stiffness  surface superquadric gaussianCurvature yes tangential_damping off

However , the radius that it is using for the forces calculations is the same as volume equivalent radius. Similarly I tried with meanCurvature yes and with CurvatureLimitFactor as more too , but even then the volume equivalent radius is being used...

Hi
I have re-installed LIGGGHTS-flexible fibers version (https://github.com/schrummy14/LIGGGHTS_Flexible_Fibers.git) on my win10 pc using Ubuntu app. After compilation I am able to run the tutorial examples, however, when I try to run model for my problem, I get the following error.
Strange thing is that I was able to run the same code before. Also, my PC has 12 cores but I am not able to allocate more than 5 cores for the run. All the above problems were not there previously.

Dear LIGGGHTS users,

In my granular systems, the largest particle diameter is 50 times the smallest particle diameter, and it is inefficient to use a single set of bins. For example, the simulation time of a mono disperse particle system is much shorter than that of binary particle system with the same particle number.