LIGGGHTS® - User Forum

I have a small simulation running with a fix massflow/mesh command which I assume is running correctly because it spits out numbers. However, I don't understand what the numbers mean, and the manual page only confuses me more. For example, it says the second vector component is a particle count, but the second number is my output is a small decimal.

Please help me understand this output, or tell what other fixes or computes I need to do to it. Please see my output data attached below.

Hi everybody,
i have a problem with implementing the "gran model hook/stiffness tangential history" model:
If i replace "hook" with "hertz" curiously the program works fine.

Here's the first part of my input-script:
atom_style granular
boundary f f f
newton off
atom_modify sort 0 0

communicate single vel yes
units si
processors 5 2 1

I'm trying to simulate a particle flow where I roughly know the distribution of particle size (vendor supplies a table of mesh size and mass %). While the range of particle size is decently large - probably about a max of 4:1 between largest:smallest: - the mass % at those extremes is fairly small.

Anyways, I'm trying to use multiple fix particletemplates for the differing mesh sizes, but I either seem to encounter an error messege saying:

ERROR: Cannot use neighbor bins - box size << cutoff (../neighbor.cpp:1670)

or

Hey everyone there,

I am doing a simulation of a cylindrical shear cell which needs 68000 particles to operate. Unfortunately i can't handle this amount with my hardware so the idea was to cut out the half or a quarter of the cell.

The problem is, that i found no way to define periodic boundary conditions for this special case. Is there a workaround? Can anybody tell me if it is possible to do a simulation of a part of a cylinder?

Thanks in advance
Stephan

linux newbie here. trying to do a git pull to get the 3.0.2 version of liggghts. performing git pull from my install directory (~/home/USERNAME/documents/liggghts - this is installed on a cygwin setup) but I get an error saying:

Updating 3fab782..3ec8c7f
error: Your local changes to the following files would be overwritten by merge:
src/style_pair.h
src/version_liggghts.h
Please, commit your changes or stash them before you can merge.
Aborting

What am I missing/doing wrong?

Hi All,

After completion of LIGGGHTS simulation, to see the results on paraview, i am trying to convert the output files into vtk format
in the post folder. But it is giving the following error.

naren@ubuntu:~/LIGGGHTS/LIGGGHTS-PUBLIC/examples/LIGGGHTS/Tutorials_public/chute_wear/post$ lpp dump*.chute
aborting due to errors: Invalid or no argument given for cpunum

It worked well till now, suddenly i come across this problem.

Please help...

Thanks,

I would like to visualize a simulation of heat transfer from particle to particle using Paraview and vtk format. Is there an expedient way to do this? Perhaps editing the dump_atom_vtk.cpp code to add Temperature/Heat properties to the write_data functions would be the most optimal?

Any insight or recommendations would be extremely helpful

V/R
Quincy

Hi I have installed mpich2 with process outlined below. LIGGGHTS in installed by following the process outlined in https://github.com/CFDEMproject/LIGGGHTS-PUBLIC/wiki/Installing-LIGGGHTS...

Hi I have installed mpich2 with process outlined below. LIGGGHTS in installed by following the process outlined in https://github.com/CFDEMproject/LIGGGHTS-PUBLIC/wiki/Installing-LIGGGHTS...

Hi, everyone here.
i have several quite basic questions: