LIGGGHTS® - User Forum

Which compute styles, fix styles, and pair_styles are necessary or useful to simulate rotating geometries like Ball mills? I want to simulate a Ball mill with 2, 4, 6, and 8 lifter as well as with different radii (Attached Fig.). Any suggestion would be appreciated.

Hello all,
Thanks in advance. I have been using LIGGGHTS for quite long now but after i create my restart file with LIGGGHTS 2.3 and when i restart my simulation with it fix ave/time does not work it stops without any error messages. further information about restart are, pls take a look into my code,
number of atoms - 322511,
restart code is,
#---------------------------------------------------------
log restlog.txt
variable r0 equal 0.06
variable re equal 0.075
variable rs equal 0.001
variable ht equal 0.30

Hi all,
I am currently doing a survey of contact laws implementation for granular materials. I have been reading LIGGGHTS manual and some workshop material available online, but for the moment I fail to find the equation of the "tangential component of velocity" at contacts.
It may sound a dumb question, but there are actually many possible definitions of this velocity. Any pointer to this equation in LIGGGHTS would be welcome. Thanks!

Hi All,

I have a few lines of codes which I designed to count the particle numbers in the region mid_reg. I used if & then sentences, however, I found the if-then codes only worked on run 1, not constantly updating.

Has anyone got any ideas.

Cheers,

I would like to set any small numbers (e.g., below 1e-15) to zero in my dump file. If I do not do this, paraview does not like my vtk files - I get the error: "Error reading ascii data. Possible mismatch of datasize with declaration."

Does anybody know of a simple way to do this using dump_modify or a similar command in the input script?

Hi,
I am trying to dump the contact force to vtk file in order to see the force chain by Paraview. However, it shows no snapshot. I saw that Mark Bentley had coded it. But when I install the EVTK by "python setup.py install", it shows an error as "gcc -pthread -fno-strict-aliasing -DNDEBUG -g -fwrapv -O2 -Wall -Wstrict-prototypes -fPIC -I/usr/lib/pymodules/python2.7/numpy/core/include -I/usr/include/python2.7 -c src/cevtk.c -o build/temp.linux-i686-2.7/src/cevtk.o
src/cevtk.c:4:20: fatal error: Python.h: No such file or directory
compilation terminated.

Hi!

I am running LIGGGHTS 2.2.1. Is it possible to read empty file with read_data I get error like

Reading data file ...
ERROR: Unknown identifier in data file: ȍ°¥Ô* (read_data.cpp:308)

My input file looks like
run 10000 upto every 1000 &
"read_data data/data_* add"

My data file looks like

LIGGGHTS

0 atoms

4 atom types

-0.3220.322 xlo xhi
-0.3220.322 ylo yhi
-0.6470.613 zlo zhi

Hello,
I want to simulate a direct sear box test. I get the code for the test form anther user form the platform. But when I want to run the code I get the following error message:

[zieher@ifas-parallel lammps]$ '/usr/lib64/liggghts_1p5p3/liggghts_1p5p3/src/lmp_fedora' < in.f0.4_90Kpa_0.7
LIGGGHTS 1.5.3 based on lammps-10Mar10
Created orthogonal box = (-0.2 -0.3 -0.1) to (0.2 0.8 0.1)
1 by 1 by 1 processor grid
0 atoms in group nve_group

Hi,
I am trying to compute contact force with paticles through the compute/gran/local command. I have use a loop command and when it loop, it shows an error as "ERROR: Need to define compute pair/gran/local or wall/gran/local before first run (compute_pair_gran_local.cpp:91)". Does anyone know how to modified it? I have attached my input file. Thanks.

shokeyi

Hi,

Although our great author told us that the "balance" command would not work with some LIGGGHTS features, I still want to have a try to check whether it works in my case.

While now I can not download previous version and can not find those files. So could anyone send them to me if convenient?

Thank you very much!!

My E-mail is li900@purdue.edu

Best

Liang