LIGGGHTS® - User Forum

Hi every one

I have small clarification in liggghts compute command
why it is used?
what are the outcome of using this command?
where are the results?

please explain me about this command in briefly

with regards
Dinesh Kumar

I am quite confused why I cannot put in pxx pyy pzz etc. as the keywords to obtain the internal stress state of the periodic cell? I tried other keywords and finally find the the pxx pyy pzz are not included in the source code (am I right?). I am wondering why it is not included in the source code as it is basic and important key values.

LAMMPS are for particle size in atomic range (angstrom). What is the minimum size of particle that can be inserted in LIGGGHTS? Most of the tutorials takes millimetre sized particles. Can we take nano to sub micron size of particles in LIGGGHTS?

ERROR: Unknown command: info system (../input.cpp:258)
I am wondering whether it is a command for premium version.

Is there no way to delete regions? The documentation says that I should be able to delete a region with "region region_name delete" but when I use such a command I get an error saying I used an illegal region command.

I also am aware the documentation says deleting a region is not usually necessary, but in my case I need to delete a region and create a new one by the same name within a loop.

I'm trying to calculate the minimum height amongst different regions in my simulation. For each region, I use "compute region_height all reduce/region region_name max z" to calculate the highest particle. Now I'm trying to find the minimum of height 1, height 2, height 3, and so on. There doesn't seem to be a way I can simply call minimum(height1,height2,height3). Is there any built-in function or work-around that will allow me to find the minimum amongst different global scalars?

Is there anyone using membrane boundary in liggghts? Just like this youtube video https://www.youtube.com/watch?v=mltNl2AphNk.
Which command should I use to bond these particles as a membrane?

I'm noticing that the code crashes pretty early in a simulation if I have multiple cores across a dimension having periodic boundary conditions. Is this a known issue and does anyone have an idea why this tends to happen? It seems that this only occurs with multisphere particles but not with regular spheres.

Greetings,
I tried to run the shear cell example on a 3.6.0 build. Unfortunately, I am getting the following error. I would be extremely grateful if you could help me out with this.

Import and parallelization of mesh cad2 containing 720 triangle(s) successful
ERROR on proc 0: assertion failed (../region_neighbor_list_I.h:156)

I have listed the echo output below.

Cheers
Jagir

Hi,
I am working on multi-sphere particle simulation. when i run the simulation it shows some of particles are suspended/stick with walls and impeller of mixer and do not settle down through out the simulation.
kindly help me
thanks in advance