LIGGGHTS® - User Forum

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.

Do the restart/write_restart and read_restart commands reset the atom IDs?
So, will a particle with a certain ID have the same ID if I am continuing my simulation using read_restart?

Best regards,
Azamat

Hello Liggghts forum,
I tried to save some variables in csv format which are mentioned below.
While running simulation,
I got an error.
I think I did mistake while including ' jump command and label'

Could you kindly help me to solve this problem?

Thank you so much

Hi. I have been trying to use six servo-controlled mesh walls to prepare an isotropic sample with a target pressure of 100kPa but encounter an issue that I could not prepare a "stable" sample.

Dear LIGGGHTS users!
I want to use the variable command to include and exclude the specific particles from a group, and I used the similar commands like that in the Docs as following:

compute 1 all pe/atom
compute 2 all reduce sum c_1
thermo_style custom step temp pe c_2
run 0
variable eatom atom "c_1 > -3.0"
group hienergy variable eatom

Dear LIGGGHTS users,

I am simulating packing systems with a very wide range of particle size, and use "neighbor 0.002 multi"+"communicate multi vel yes". However, the output kinetic energy and pressure are both zero. When using "neighbor 0.002 bin"+"communicate single vel yes", the output kinetic energy and pressure are not zero.

Could you please tell me the reason?
Any help will really be appreciated.

Best wishes
June

Apologies for the same issue again.

According to error I know that I have to change my particle insertion region but I couldn't figure it out right region in my simulation. i am totally stuck here.
It would be a great help if anyone could let me to know the idea to fix my error.

Error:

I have been running simple shear stress simulations in LIGGGHTS using moving layers of particles along the top and bottom of the domain to mimic a Lees-Edwards boundary condition. I am able to get reasonable agreement with kinetic theory for normal and shear stresses for spherical particles using the compute stress/atom command. However, when I create spherical superquadric particles to run the same cases, I would expect very close to the same, exact result.

Dear LIGGGHTS users,

I want to relax the packing system statistically by minimizing the energy, and used the command "minimize 1.0e-4 1.0e-6 10000 100000".
The error message is "Minimization could not find thermo_pe compute". The manual explains this error as "This compute is created by the thermo command. It must have been explicitly deleted by a uncompute command". But I have not deleted this compute.

I am trying to run a simple simulation with a mesh file which is available in example as simple_chute.stl.
Now I am able to run simulation after changing the boundary to m m m but all of my particles are falling outside of domain.
Can anyone help me to fix this problem?

This is my script:

###############################################
# Example of LIGGGHTS #
# Flow only two particles in a plane surface #
###############################################

# Initialize