LIGGGHTS® - Developer Forum

Hello Everyone,

I wanted to change the equation of cohesion model in liggghts, so I changed the equation of Force = Cohesive Energy Density * Area in cohesion_model_sjkr.h (lines 98 & 99). Do I need to change any other file associated with it before compiling ? What file in addition to cohesion_model_sjkr.h I need to change in order to implement this new equation of cohesion?

I am new to liggghts and C++, so please let me know what should I do.

Thanks&Regards,
Abdul.

Hi guys!

I want to compute the stress sum over each mesh triangle, but I can't find where the wall/particle contact stress is stored.

Is there a way to access it?

Thank you!

I'm trying to compile LIGGGHTS on a Mac Mini running macOS High Sierra 10.13.6 and have come across this issue:

I'm trying to add capability for self gravitation for N-Body dust simulations. As I understand it, LIGGGHTS includes coulombic long range solvers, backed up by the "getting started" section of the documentation, however, I've been having a difficult time finding where in the SRC the long range solvers are implemented, such that I can modify them as needed. It should be relatively straight forward, as they are both solving poisson equations, gravity should be as simple as changing a constant, adding a minus sign, and swapping m for q.

Hello everyone, I tell you that I am a new user in LIGGGHTS, and I am working on a program modeling a system consisting of a belt, barriers, box and board. In the latter, the particles fall to the belt that moves at 5 m / s, where they are finally deposited in the box. However, the program does not run, because the following messages appear:

"0 atoms group group" ... .. (does the "group" command work correctly?)
"Error on proc 0: Too many neighbor bins (../neigbor.cpp:1776) .......... (What happens to the neighbors?)

Hi guys,

I am trying to extract the total cohesion force(easo capillary) for each atom, but I currently do not know how the force is accumulated for each atom.

Dear all,

I just implemented the Van Der Waals force model proposed in this paper 'Yang, R., et al. (2000). Physical review E 62(3): 3900., Equ.8'. What I did is as following:

1. Implemented this model as one of the cohesion models of LIGGGHTS.
2. Registered some parameters used in the model in 'global_properties.h' and 'global_properties.cpp'.

Finally, I recompiled this model in LIGGGHTS successfully using 'make clean-auto and make -j32 auto'. However, when I tried to preform some DEM simulations using this newly implemented model, I got this error:

I have designed a box and trying to insert particles. But after computation, on viewing through PARAVIEW i cannot find the particles. I am new to LIGGGTS, any assistance at all appreciated. attaching herwith the code and files. the stl files are uploaded as pdf.

Hello,
in the doc for the "gran model hertz model" there is the flag
disableNormalWhenBonded
How can I gain access to this?
When I tried adding it to an input script, I received the error
pair_style gran model hertz disableNormalWhenBonded on tangential history
ERROR on proc 0: Could not find bond history offset (../normal_model_hertz.h:134)

Thanks for all the help!

Hi All,

I try to install Open MPI, which is prerequiste for liggghts. Some info about my current Suse version :

NAME="SLED"
VERSION="12-SP3"
VERSION_ID="12.3"
PRETTY_NAME="SUSE Linux Enterprise Desktop 12 SP3"
ID="sled"

I installed Open MPI 1.6 by typing

./configure --prefix=$HOME/openmpi
make all
make install