LIGGGHTS® - User Forum

Hi everyone,

I am trying to simulate an assembly of bonded particles and using the software LIGGGHTS_Flexible_Fibers by mshramm. The script of my simple insertion simulation is:

# Constant settings
atom_style hybrid granular bond/gran n_bondtypes 1 bonds_per_atom 6
atom_modify map array
boundary f f f # will change to f f f boundary to save time
newton off
#echo both
communicate single vel yes
units si

region reg block -0.05 0.05 -0.035 0.035 0.0 0.025 units box
create_box 2 reg

Hello,

I am running a simulation about granular flow with around 20,000 particles, among which there is one special particle (called "intruder"). Right now, I would like to change the shape of the "intruder" from sphere to cylinder (superquadric), while keeping the shape of other particles as spheres. So how could I do it?

My current "intruder" particle creating code are like:

create_atoms 2 single ${xintr} ${yintr} ${zintr}
group intruder type 2
set group intruder diameter ${dl} density ${rho}

Thanks!

I am trying to create a simulation where particle will take some specific position.

Primary job terminated normally, but 1 process returned
a non-zero exit code. Per user-direction, the job has been aborted.
--------------------------------------------------------------------------

SIGINT/SIGTERM caught - Writing restart on next occasion and quitting after that.
--------------------------------------------------------------------------
mpirun noticed that process rank 0 with PID 0 on node user exited on signal 9 (Killed).

While I was running a script, the system crashed with the above message.

ERROR: Invalid atom style (/build/liggghts-YO7u74/liggghts-3.8.0+repack1/src/atom.cpp:459)
I an trying to use Superquadric particles but I am unable to use even though I enabled it in make file and recompiled the code. Can anyone please tell why does the error pops up?

Hello all,
I am Tarun from India. I wanted to install Aspherix basic in my system. But, while purchasing, I noticed that there is no option for "India" in the "Region" drop-down. Thus, I could not buy it. Can anyone please help me with this???

I really appreciate any help you can provide.

Regards,
Tarun

Hello Community,

I have a question regarding the implementation of the contact models. Like I understand and has been discussed allready in the forum Liggghts follows the integral implementation of the spring force according Di Renzo and Di Margio. Thats fine. I am more unsure about the implementation of the damping force and the coulomb criterion.

Like i understood from literature there are 2 ways:

1) First check tangential spring forces for coloumb considering the normal spring force and than add the damper afterwards in both cases if necessary:

Hello,

Does LIGGGHTS have the linear spring-dashpot contact model? If not, how can it be implemented?

Hello everyone,

I have installed LIGGGHTS successfully by the file 'makefile.auto' in source. And I can successfully run the examples provided in the examples/LIGGGHTS/Tutorials_public such as the chute_wear by the command 'lmp_auto < in.chute_wear'. But for some reasons I'd like to build LIGGGHTS as a shared library. Having done this, when I tapped 'lmp_auto' in the terminal, it got error as 'bash: lmp_auto: command not found'. However, command 'python chute_wear.py in.chute_wear' ran with no errors, where 'chute_wear.py' is a file shown as follows